第9课时——公式法,根的判别式及根与系数的关系

第9课时——公式法,根的判别式及根与系数的关系 课题 2.3 公式法 课型 新授课 课时 教师 1(一元二次方程的求根公式的推导; 教学 2(会用求根公式解一元二次方程。 目标 重点 一元二次方程的求根公式( 2难点 求根公式的条件:b,4ac0。 , 教法 合作探究 学法 合作交流 时间 2011年 7月 日 一、学习一、复习 创设困惑 1、用配 方法 快递客服问题件处理详细方法山木方法pdf计算方法pdf华与华方法下载八字理论方法下载 解一元二次方程的步骤有哪些, 情景 记录 混凝土 养护记录下载土方回填监理旁站记录免费下载集备记录下载集备记录下载集备记录下载 2引入2、用配方法解方程:x,7x,18,0 新课 21、用配方法求解方程:ax，bx，c,0(a?0) 2一般地，对于一元二次方程ax，bx，c,0(a?0)， 2当b,4ac 时，它的根是x, 。 2注意:当b,4ac 时，一元二次方程无实数根。 2、公式法: 二、 利用求根公式解一元二次方程的方法叫做公式法。 讲授 新课 3、例题讲析: 2例:解方程:x―7x―18,0 2例:解方程:2x，7x,4 am, ferved to the installation acceptance before they can betape measure pipe and elevation. Preliminary fixing of seams, taking into account the pipe Center not to shift, steel pipe setall the axis reference points for installation of control points should be clear, strong and easy to use, and should be pres2007 5th. 2) is used to measure height, distance and ins-ipe installation work shall comply with the provisions of chapter DL/T5017lation and use of equipment, installation, temporary works, quality inspection procedures and security measures, and so on. Pinstaliation of the DL5017 specification. (4) steel pipe installation step 1) in submitting construction plans, should detail pipe ck and clearance, hammer, level and line pipe and steel tape repeated orifice and pipe straightness. Fixed pipe after the dev ls cheion steel pipe joints not to shift. Pipe joints with wedge plates, z font code and screw TURNBUCKLE tie, also by shearing tooixed with angle (angle iron against the base at one end and temporary welding of welding and steel tubes), guaranteed by sectby the buttress of the town center and vertical, steel pipe is in place, with strings, hammer line, horizontal pipe and steeluired n units to provide the town Pier and vertical control points, after it has been checked, survey release tube installation req: lifting ? ? connection ? adjust ? fixed touch up ? ? ? welding ? cleaning polishing completed. According to the constructiollowsel wire rope for lifting and towing ropes, hauling, lifting machines of 5 tons *2. 5) installation installation process as focable crane 3 ton machine, using a cable machine hoisting steel pipe. Cable selection ? 24mm* main cable, with ? 15mm ste tallation. 4) installation erected on site designreinforced concrete. Ming following half of the starting unit, from the plant to the reverse direction of flow section on ins-ight deviation control within 2mm. Such as steel, reinforcing Tian Ding, concreten. Hemagnetic drill/hand ... Center height installation for base, each installed segment both up and down, left and right dimensio hop angle grinder P125 4 Germany 2011 60 good shop top 0.5T~10T 12 2012.12 20,000 pounds China's 2009 50 good shop 2012.12 21works11 3T/5T 12 13 6 good workshop 2012.12 18 high pressure Airless spraying machine King56:1 1 Shanghai 2005 2012.12 19 25 good 113 good workshop rust sandblasting machine 1 set 2008 2012.12 17 123 good workshop manual hoist, Shanghai Zhejiang Wuling 20 2 2 Shanghai 2009 2012.12 16-6/1.5M3 1 2012.12 15 160 good shop air spray gun (zinc) ZQP-r V1 三、随时221、用公式法解方程x+4x=2,其中求的b-4ac的值是( ) 322应用纠错 深化 A.16 B. 4 C. D.64 32, 222、用公式法解方程x=-8x-15，其中b-4ac= ，方程的根是 .。 23、用公式法解方程3x+4=12x，下列代入公式正确的是( ) ,12,144,1212,144,12A.x= B. x= 1.21.222 12,144,4812,144，12C. x= D. x= 1.21.226 24、三角形两边长分别是3和5，第三边的长是方程3x-10x-8=0的根，则此三角形是 三角形. 2x，x,25、如果分式的值为零，那么x= . x,1 6、用公式法解下列方程: 2 2(1) 3 y-y-2 = 0(2) 2 x+1 =3x 2(3)4x-3x-1=x-2 (4)3x(x-3)=2(x-1)(x+1) 二、新知识你都掌握了吗,课后来这里显显身手吧～ 2227、把方程(2x-1)(x+3)=x+1化为ax + bx + c = 0的形式，b-4ac= ，方程的根是 . 8、方程(x-1)(x-3)=2的根是( ) 333A. x=1,x=3 B.x=22 C.x=2 D.x=-22 ,,,12 259、关于x的一元二次方程x+4x-m=0的一个根是-2，则m= ，方程的另一个根是 . r V-6/1.5M3 1 2012.12 15 160 good shop air spray gun (zinc) ZQP-2 2 Shanghai 2009 2012.12 16 113 good workshop rust sandblasting machine 1 set 2008 2012.12 17 123 good workshop manual hoist, Shanghai Zhejiang Wuling 2011 3T/5T 12 13 6 good workshop 2012.12 18 high pressure Airless spraying machine King56:1 1 Shanghai 2005 2012.12 19 25 good workshop angle grinder P125 4 Germany 2011 60 good shop top 0.5T~10T 12 2012.12 20,000 pounds China's 2009 50 good shop 2012.12 21 magnetic drill/hand ... Center height installation for base, each installed segment both up and down, left and right dimension. Height deviation control within 2mm. Such as steel, reinforcing Tian Ding, concrete-reinforced concrete. Ming following half of the starting unit, from the plant to the reverse direction of flow section on installation. 4) installation erected on site design cable crane 3 ton machine, using a cable machine hoisting steel pipe. Cable selection ? 24mm* main cable, with ? 15mm steel wire rope for lifting and towing ropes, hauling, lifting machines of 5 tons *2. 5) installation installation process as follows: lifting ? ? connection ? adjust ? fixed touch up ? ? ? welding ? cleaning polishing completed. According to the construction units to provide the town Pier and vertical control points, after it has been checked, survey release tube installation required by the buttress of the town center and vertical, steel pipe is in place, with strings, hammer line, horizontal pipe and steel tape measure pipe and elevation. Preliminary fixing of seams, taking into account the pipe Center not to shift, steel pipe seam, fixed with angle (angle iron against the base at one end and temporary welding of welding and steel tubes), guaranteed by section steel pipe joints not to shift. Pipe joints with wedge plates, z font code and screw TURNBUCKLE tie, also by shearing tools check and clearance, hammer, level and line pipe and steel tape repeated orifice and pipe straightness. Fixed pipe after the deviation of the DL5017 specification. (4) steel pipe installation step 1) in submitting construction plans, should detail pipe installation and use of equipment, installation, temporary works, quality inspection procedures and security measures, and so on. Pipe installation work shall comply with the provisions of chapter DL/T5017-2007 5th. 2) is used to measure height, distance and install the axis reference points for installation of control points should be clear, strong and easy to use, and should be preserved to the installation acceptance before they can be 210、若最简二次根式和是同类二次根式，则的值为( ) 8m，2m,7 A.9或-1 B.-1 C.1 D.9 11、用公式法解下列方程: 22(1)x-2x-8=0; (2)x+2x-4=0; 2(3)2x-3x-2=0; (4)3x(3x-2)+1=0. 三、本节课你学到了什么, 小结 反馈 课题 跟的判别式,补充, 课型 新授课 课时 教师 教学(一)使学生理解一元二次方程的根的判别式，知道所判别的对象是什么; 目标 (二)使学生会运用根的判别式，在不解方程的前提下判别根的情况. 重点 一元二次方程的根的判别式的运用. 难点 对一元二次方程的根的判别式的结论的理解. 教法 合作探究 学法 合作交流 时间 2011年 7月 日 一、1.请同学们回想一下，我们用求根公式法解一元二次方程时，在把系数代入求根公式前，必学习创设须写出哪两步?为什么要先写这两步? 困惑情景 例 用求根公式法解方程(教师把这个过程写在黑板上) 记录 2引入 2x+10x-7=0. 新课 2.为什么在把系数代入求根公式前，要先写?式、?式这两步? 22+bx+c=0(a?0)中，代数式b-4ac起着重 1. 从上面的解释可见，在一元二次方程ax 要的作用，我们把它叫做根的判别式，通常用记号 表示，即 22b,4ac Δ=b-4ac(注意不是 Δ= 2、根的判别式是判别根的什么? 二、下面我们用三个定理来表示(我们通常把记号AB表 , 讲授示为A是命题的条件，B是命题的结论)于是有: 2新课 定理1 ax+bx+c=0(a?0)中，Δ0方程有两个不等实数根. ,2 定理2 ax+bx+c=0(a?0)中，Δ=0方程有两个相等实数根. , 2 定理3 ax+bx+c=0(a?0)中，Δ,0方程没有实数根. , 注意:这三个定理 反过来也成立，我们还得到三个定理，那就是 2ax+bx+c=0(a?0)中，方程有两个不等实数根Δ,0. , 2 ax+bx+c=0(a?0)中，方程有两个相等实数根Δ,0. ,2 ax+bx+c=0(a?0)中，方程没有实数根,Δ,0. r V-6/1.5M3 1 2012.12 15 160 good shop air spray gun (zinc) ZQP-2 2 Shanghai 2009 2012.12 16 113 good workshop rust sandblastin g machine 1 set 2008 2012.12 17 123 good workshop manual hoist, Shanghai Zhejiang Wuling 2011 3T/5T 12 13 6 good workshop 2012.3 12 18 high pressure Airless spraying machine King56:1 1 Shanghai 2005 2012.12 19 25 good workshop angle grinder P125 4 Germany 2011 60 good shop top 0.5T~10T 12 2012.12 20,000 pounds China's 2009 50 good shop 2012.12 21 magnetic drill/hand ... Center height installation for base, each installed segment both up and down, left and right dimension. Height deviation control within 2mm. Such as steel, reinforcing Tian Ding, concrete-reinforced concrete. Ming following half of the starting unit, from the plant to the reverse direction of flow section on installation. 4) installation erected on site design cable crane 3 ton machine, using a cable machine hoisting steel pipe. Cable selection ? 24mm* main cable, with ? 15mm steel wire rope for lifting and towing ropes, hauling, lifting machines of 5 tons *2. 5) installation installation process as follows: lifting ? ? connection ? adjust ? fixed touch up ? ? ? welding ? cleaning polishing completed. According to the construction units to provide the town Pier and vertical control points, after it has been checked, survey release tube installation required by the buttress of the town center and vertical, steel pipe is in place, with strings, hammer line, horizontal pipe and steel tape measure pipe and elevation. Preliminary fixing of seams, taking into account the pipe Center not to shift, steel pipe seam, fixed with angle (angle iron against the base at one end and temporary welding of welding and steel tubes), guaranteed by section steel pipe joints not to shift. Pipe joints with wedge plates, z font code and screw TURNBUCKLE tie, also by shearing tools check and clearance, hammer, level and line pipe and steel tape repeated orifice and pipe straightness. Fixed pipe after the deviation of the DL5017 specification. (4) steel pipe installation step 1) in submitting construction plans, should detail pipe installation and use of equipment, installation, temporary works, quality inspection procedures and security measures, and so on. Pipe installation work shall comply with the provisions of chapter DL/T5017-2007 5th. 2) is used to measure height, distance and install the axis reference points for installation of control points should be clear, strong and easy to use, and should be preserved to the installation acceptance before they can be 显然，定理1与定理4，互为逆定理，定理2与定理5，互为逆定理.定理3与定理6， 互逆定理. 定理1，2，3的作用是用已知方程的系数，来判断根的情况. 定理4，5，6的作用是已知方程根的情况，来确系数之间的关系，进而求出系数中某些字母的值. 运用根的判别式解题举例 例1 不解方程，判别下列方程根的情况. 22 (1) 2x+3x-4=0; (2) 16y2+9=24y; (3)5(x+1)-7x=0. 22例2 已知方程2x+(k-9)x+(k+3k+4)=0有两个相等的实数根，求k值，并求出方程的解. 22例3 若关于x的方程x+2(a+1)x+(a+4a-5)=0有实数根，试求正整数a的值. 三、1.下列方程中，有两个相等实数根的方程是( ). 随时 应用纠错 深化 2 2.若方程(k2-1)x-6(3k-1)+72=0有两个不同的正整数根，则整数k的值是( ). 2222 3.若a,b,c互不相等，则方程(a+b+c)x+2(a+b+c)x+3=0( ). (A) 有两个相等的实数根 (B) 有两个不相等的实数根 (C) 没有实数根 (D) 根的情况不确定 4.不解方程，判别下列方程的根的情况: 2 5.已知关于x的方程x+(2m+1)x+(m-2)2=0.m取什么值时， (1)方程有两个不相等的实数根? (2)方程有两个相等的实数根? (3) 方程没有实数根? 2 6.k取什么值时，方程4x-(k+2)x+k-1=0有两个相等的实数根?并求出这时方程的根. 2 7.求证:关于x的方程x+(2k+1)x+k-1=0有两个不相等的实数根. 21(已知关于x的一元二次方程ax+2x+1=0有两个不相等的实数根，则a的取值范围是( )。 A、a<1 B、a>1 C、a<1且a?0 D、a<0 2 2(关于x的一元二次方程kx-3x+2=0有两个相等的实根，则k应满足是( )。 A、k=0 B、k?0 C、k=- D、k= r V-6/1.5M3 1 2012.12 15 160 good shop air spray gun (zinc) ZQP-2 2 Shanghai 2009 2012.12 16 113 good workshop rust sandblasting machine 1 set 2008 2012.12 17 123 good workshop manual hoist, Shanghai Zhejiang Wuling 2011 3T/5T 12 13 6 good workshop 2012.12 18 high pressure Airless spraying machine King56:1 1 Shanghai 2005 2012.12 19 25 good workshop angle grinder P125 4 Germany 2011 60 good shop top 0.5T~10T 12 2012.12 20,000 pounds China's 2009 50 good shop 2012.12 21 magnetic drill/hand ... Center height installation for base, each installed segment both up and down, left and right dimension. Height deviation control within 2mm. Such as steel, reinforcing Tian Ding, concrete-reinforced concrete. Ming following half of the starting unit, from the plant to the reverse direction of flow section on installation. 4) installation erected on site design cable crane 3 ton machine, using a cable machine hoisting steel pipe. Cable selection ? 24mm* main cable, with ? 15mm steel wire rope for lifting and towing ropes, hauling, lifting machines of 5 tons *2. 5) installation installation process as follows: lifting ? ? connection ? adjust ? fixed touch up ? ? ? welding ? cleaning polishing completed. According to the construction units to provide the town Pier and vertical control points, after it has been checked, survey release tube installation required by the buttress of the town center and vertical, steel pipe is in place, with strings, hammer line, horizontal pipe and steel tape measure pipe and elevation. Preliminary fixing of seams, taking into account the pipe Center not to shift, steel pipe seam, fixed with angle (angle iron against the base at one end and temporary welding of welding and steel tubes), guaranteed by section steel pipe joints not to shift. Pipe joints with wedge plates, z font code and screw TURNBUCKLE tie, also by shearing tools check and clearance, hammer, level and line pipe and steel tape repeated orifice and pipe straightness. Fixed pipe after the deviation of the DL5017 specification. (4) steel pipe installation step 1) in submitting construction plans, should detail pipe installation and use of equipment, installation, temporary works, quality inspection procedures and security measures, and so on. Pipe installation work shall comply with the provisions of chapter DL/T5017-2007 5th. 2) is used to measure height, distance and install the axis reference points for installation of control points should be clear, strong and easy to use, and should be preserved to the installation acceptance before they can be 22 3(关于x的方程m(x+x+1)=x+x+2有两个相等的实数根，则m的值为( ) 。 A、 B、1 C、- D、或1 22 4(若方程k(x-2x+1)-2x+x=0有实数根，则( )。 A、k>- B、k>-且k?2 C、k?- D、k?- 且k?2 2 5(方程x-4x+=0有根的情况是( ) A、有两个不相等的实数根 B、有两个相等的实数根 C、没有实数根 D、有一个实数根 6(下列方程中，有两个相等实数根的一元二次方程是( )。 2 A、3x-4x-1=0 2 B、x+3+2=2 x+2x 3 C、x-2x+5=0 2 D、x+ x=1 2 7(若方程x+x+n=0有两个相等的实数根，那么 的值为( )。 A、- B、 C、-4 D、4 22 8(已知关于x的方程x+3(m-1)x-2m-4m+=0(m为实数)，则该方程( )。 A、无实数根 B、有两个相等实数根 C、有不等的两实数根 D、不能确定有无实数根 三、本节课你学到了什么, 小结 反馈 课后 反思 r V-6/1.5M3 1 2012.12 15 160 good shop air spray gun (zinc) ZQP-2 2 Shanghai 2009 2012.12 16 113 good workshop rust sandblastin g machine 1 set 2008 2012.12 17 123 good workshop manual hoist, Shanghai Zhejiang Wuling 2011 3T/5T 12 13 6 good workshop 2012.5 12 18 high pressure Airless spraying machine King56:1 1 Shanghai 2005 2012.12 19 25 good workshop angle grinder P125 4 Germany 2011 60 good shop top 0.5T~10T 12 2012.12 20,000 pounds China's 2009 50 good shop 2012.12 21 magnetic drill/hand ... Center height installation for base, each installed segment both up and down, left and right dimension. Height deviation control within 2mm. Such as steel, reinforcing Tian Ding, concrete-reinforced concrete. Ming following half of the starting unit, from the plant to the reverse direction of flow section on installation. 4) installation erected on site design cable crane 3 ton machine, using a cable machine hoisting steel pipe. Cable selection ? 24mm* main cable, with ? 15mm steel wire rope for lifting and towing ropes, hauling, lifting machines of 5 tons *2. 5) installation installation process as follows: lifting ? ? connection ? adjust ? fixed touch up ? ? ? welding ? cleaning polishing completed. According to the construction units to provide the town Pier and vertical control points, after it has been checked, survey release tube installation required by the buttress of the town center and vertical, steel pipe is in place, with strings, hammer line, horizontal pipe and steel tape measure pipe and elevation. Preliminary fixing of seams, taking into account the pipe Center not to shift, steel pipe seam, fixed with angle (angle iron against the base at one end and temporary welding of welding and steel tubes), guaranteed by section steel pipe joints not to shift. Pipe joints with wedge plates, z font code and screw TURNBUCKLE tie, also by shearing tools check and clearance, hammer, level and line pipe and steel tape repeated orifice and pipe straightness. Fixed pipe after the deviation of the DL5017 specification. (4) steel pipe installation step 1) in submitting construction plans, should detail pipe installation and use of equipment, installation, temporary works, quality inspection procedures and security measures, and so on. Pipe installation work shall comply with the provisions of chapter DL/T5017-2007 5th. 2) is used to measure height, distance and install the axis reference points for installation of control points should be clear, strong and easy to use, and should be preserved to the installation acceptance before they can be 课题 根与系数的关系(补充) 课型 新授课 课时 教师 教学1、掌握一元二次方程两根的和、两根的积与系数的关系。 目标 2、能根据根与系数的关系式和已知一个根的条件下～求出方程的另一根～以及方程中的 未知系数。 3、会利用根与系数的关系求关于两根代数式的值。 重点 一元二次方程根与系数的关系及应用 难点 探索一元二次方程根与系数的关系 教法 合作探究 学法 合作交流 时间 2011年 7月 日 一、1、一元二次方程的一般形式是什么, 学习创设 困惑情景2、一元二次方程的求根公式是什么, 记录 引入 新课 3、如何判断一元二次方程根的情况, 探索规律 1、议一议:补全下列表格，并回答问题 方程 方程的两根 X+ X XX 1 21 × 22?x-2x+1=0 X= X = 122?x+3x-10=0 X= X = 122?x+5x+4=0 X= X = 12 2= X = X12?2x+5x+3=0 2= X = X12?3x-2x-2=0 问题:观察两根之和，两根之积与方程的系数之间有什么关系, 2、猜一猜:请根据以上的观察猜想 二、2方程ax+bx+c=0(a?0)的两根x，x与a、b、c之间的关系:____________. 12讲授 新课 3、验证结论: 2设X，X为方程ax+bx+c=0(a?0)的两个实数根，证明上述结论 1 2 r V-6/1.5M3 1 2012.12 15 160 good shop air spray gun (zinc) ZQP-2 2 Shanghai 2009 2012.12 16 113 good workshop rust sandblasting machine 1 set 2008 2012.12 17 123 good workshop manual hoist, Shanghai Zhejiang Wuling 2011 3T/5T 12 13 6 good workshop 2012.12 18 high pressure Airless spraying machine King56:1 1 Shanghai 2005 2012.12 19 25 good workshop angle grinder P125 4 Germany 2011 60 good shop top 0.5T~10T 12 2012.12 20,000 pounds China's 2009 50 good shop 2012.12 21 magnetic drill/hand ... Center height installation for base, each installed segment both up and down, left and right dimension. Height deviation control within 2mm. Such as steel, reinforcing Tian Ding, concrete-reinforced concrete. Ming following half of the starting unit, from the plant to the reverse direction of flow section on installation. 4) installation erected on site design cable crane 3 ton machine, using a cable machine hoisting steel pipe. Cable selection ? 24mm* main cable, with ? 15mm steel wire rope for lifting and towing ropes, hauling, lifting machines of 5 tons *2. 5) installation installation process as follows: lifting ? ? connection ? adjust ? fixed touch up ? ? ? welding ? cleaning polishing completed. According to the construction units to provide the town Pier and vertical control points, after it has been checked, survey release tube installation required by the buttress of the town center and vertical, steel pipe is in place, with strings, hammer line, horizontal pipe and steel tape measure pipe and elevation. Preliminary fixing of seams, taking into account the pipe Center not to shift, steel pipe seam, fixed with angle (angle iron against the base at one end and temporary welding of welding and steel tubes), guaranteed by section steel pipe joints not to shift. Pipe joints with wedge plates, z font code and screw TURNBUCKLE tie, also by shearing tools check and clearance, hammer, level and line pipe and steel tape repeated orifice and pipe straightness. Fixed pipe after the deviation of the DL5017 specification. (4) steel pipe installation step 1) in submitting construction plans, should detail pipe installation and use of equipment, installation, temporary works, quality inspection procedures and security measures, and so on. Pipe installation work shall comply with the provisions of chapter DL/T5017-2007 5th. 2) is used to measure height, distance and install the axis reference points for installation of control points should be clear, strong and easy to use, and should be preserved to the installation acceptance before they can be (1)当满足条件 时，方程的两根是X= X= 12 (2)两根之和X+ X= 1 2 两根之积XX= 1 2 4、归纳结论: 一元二次方程根与系数的关系: 2如果x，x是一元二次方程ax+bx+c=0(a?0)的两个根，那么X+ X= ，121 2XX= 1 22如果x，x是一元二次方程x+px+q =0(a?0)的两个根，那么X+ X= ，121 2XX= 1 2 为了纪念在研究和推广这个定理中做出贡献的法国数学家韦达，又把这个定理叫 做韦达定理。 应用新知 1、基础练习:不解方程，求下列方程两根的和与两根的积各是多少, 22(1)x- 3x+1=0 ( 2)3x- 2x=2 222(3)2x+3x=0 (4)3x=1 (5) x- 3x+4=0 22、例1:已知方程3x-4x+2m-1=0的一个根是2，求方程的另一个根及m的值. 方法一 方法二 归纳:利用根与系数的关系可以解决什么问题, 222例3:已知X,X是方程2x+3x-1=0的两个根,利用根与系数的关系求x + x 的1 212值 归纳:解决此类型题目的关键是什么, r V-6/1.5M3 1 2012.12 15 160 good shop air spray gun (zinc) ZQP-2 2 Shanghai 2009 2012.12 16 113 good workshop rust sandblastin g machine 1 set 2008 2012.12 17 123 good workshop manual hoist, Shanghai Zhejiang Wuling 2011 3T/5T 12 13 6 good workshop 2012.7 12 18 high pressure Airless spraying machine King56:1 1 Shanghai 2005 2012.12 19 25 good workshop angle grinder P125 4 Germany 2011 60 good shop top 0.5T~10T 12 2012.12 20,000 pounds China's 2009 50 good shop 2012.12 21 magnetic drill/hand ... Center height installation for base, each installed segment both up and down, left and right dimension. Height deviation control within 2mm. Such as steel, reinforcing Tian Ding, concrete-reinforced concrete. Ming following half of the starting unit, from the plant to the reverse direction of flow section on installation. 4) installation erected on site design cable crane 3 ton machine, using a cable machine hoisting steel pipe. Cable selection ? 24mm* main cable, with ? 15mm steel wire rope for lifting and towing ropes, hauling, lifting machines of 5 tons *2. 5) installation installation process as follows: lifting ? ? connection ? adjust ? fixed touch up ? ? ? welding ? cleaning polishing completed. According to the construction units to provide the town Pier and vertical control points, after it has been checked, survey release tube installation required by the buttress of the town center and vertical, steel pipe is in place, with strings, hammer line, horizontal pipe and steel tape measure pipe and elevation. Preliminary fixing of seams, taking into account the pipe Center not to shift, steel pipe seam, fixed with angle (angle iron against the base at one end and temporary welding of welding and steel tubes), guaranteed by section steel pipe joints not to shift. Pipe joints with wedge plates, z font code and screw TURNBUCKLE tie, also by shearing tools check and clearance, hammer, level and line pipe and steel tape repeated orifice and pipe straightness. Fixed pipe after the deviation of the DL5017 specification. (4) steel pipe installation step 1) in submitting construction plans, should detail pipe installation and use of equipment, installation, temporary works, quality inspection procedures and security measures, and so on. Pipe installation work shall comply with the provisions of chapter DL/T5017-2007 5th. 2) is used to measure height, distance and install the axis reference points for installation of control points should be clear, strong and easy to use, and should be preserved to the installation acceptance before they can be 2三、1、已知方程5x-7x+k=0的一个根是2，求它的另一个根及K的值; 随时应用 纠错 深化 22、设x，x是方程2x+4x-3=0的两个根，利用根与系数的关系，求 12 xx21， 的值 xx12 23、若方程x,2x,1=0的两个实数根为x，x，则x+x=______( 1212 24、设一元二次方程x,6x+4=0的两实根分别为x和x，则x+x=_____，x?x=______( 121212 25、等腰三角形ABC中，BC=8，AB，AC的长是关于x的方程x,10x+m=0的两根，求m 的值( 6、如果 2是方程x2-4x+c=0的一个根～求方程的另一个根及c 的值, 27、设x，x是方程2x- 6x+3=0的两个根，利用根与系数关系，求下列各式的值: 12 22(1)x x+ xx 1212 三、本节课你学到了什么, 小结 反馈 课后 反思 r V-6/1.5M3 1 2012.12 15 160 good shop air spray gun (zinc) ZQP-2 2 Shanghai 2009 2012.12 16 113 good workshop rust sandblasting machine 1 set 2008 2012.12 17 123 good workshop manual hoist, Shanghai Zhejiang Wuling 2011 3T/5T 12 13 6 good workshop 2012.12 18 high pressure Airless spraying machine King56:1 1 Shanghai 2005 2012.12 19 25 good workshop angle grinder P125 4 Germany 2011 60 good shop top 0.5T~10T 12 2012.12 20,000 pounds China's 2009 50 good shop 2012.12 21 magnetic drill/hand ... Center height installation for base, each installed segment both up and down, left and right dimension. Height deviation control within 2mm. Such as steel, reinforcing Tian Ding, concrete-reinforced concrete. Ming following half of the starting unit, from the plant to the reverse direction of flow section on installation. 4) installation erected on site design cable crane 3 ton machine, using a cable machine hoisting steel pipe. Cable selection ? 24mm* main cable, with ? 15mm steel wire rope for lifting and towing ropes, hauling, lifting machines of 5 tons *2. 5) installation installation process as follows: lifting ? ? connection ? adjust ? fixed touch up ? ? ? welding ? cleaning polishing completed. According to the construction units to provide the town Pier and vertical control points, after it has been checked, survey release tube installation required by the buttress of the town center and vertical, steel pipe is in place, with strings, hammer line, horizontal pipe and steel tape measure pipe and elevation. Preliminary fixing of seams, taking into account the pipe Center not to shift, steel pipe seam, fixed with angle (angle iron against the base at one end and temporary welding of welding and steel tubes), guaranteed by section steel pipe joints not to shift. Pipe joints with wedge plates, z font code and screw TURNBUCKLE tie, also by shearing tools check and clearance, hammer, level and line pipe and steel tape repeated orifice and pipe straightness. Fixed pipe after the deviation of the DL5017 specification. (4) steel pipe installation step 1) in submitting construction plans, should detail pipe installation and use of equipment, installation, temporary works, quality inspection procedures and security measures, and so on. Pipe installation work shall comply with the provisions of chapter DL/T5017-2007 5th. 2) is used to measure height, distance and install the axis reference points for installation of control points should be clear, strong and easy to use, and should be preserved to the installation acceptance before they can be