初三化简求值题及答案
@鄢王2760：求10道初三分式化简求值求值题+答案. - 作业帮
东油15227324854…… [答案] 例1、化简 (08宁波市) 例2、化简: (08泸州市) = = = = = . 2、乘除型化简 例3、化简: (08年大连市改编) 分析:在解答化简问题时,我们要做到如下几点: 1、当分子、分母是多项式时,先进行分解因式; 2、进行通分; 3、进行约分,化...
@鄢王2760：谁知道有化简求值《整式加减》的题,要有答案的.大概30道左右.thanks! - 作业帮
东油15227324854…… [答案] (一)填空 3.3ab-4ab+8ab-7ab+ab=______. 4.7x-(5x-5y)-y=______. 5.23a3bc2-15ab2c+8abc-24a3bc2-8abc=______. 6.... D.以上答案都不对. (三)化简 70.(4x2-8x+5)-(x3+3x2-6x+2). 72.(0.3x3-x2y+xy2-y3)-(-0.5x3-x2y+0.3xy2). 73.-{2a2b-[3abc-(4ab...
@鄢王2760：初三数学解答题求解先化简再求值:(1+1/x - 1)除以x/x的平方 - 1,其中x= - 4 - 作业帮
东油15227324854…… [答案] [1+1/(x-1)]÷x/(x²-1) =[(x-1)/(x-1)+1/(x-1)]÷x/(x+1)(x-1) =x/(x-1)*(x+1)(x-1)/x =x+1 其中x=-4 原式=-4+1=-3
@鄢王2760：一道初三的化简求值题目,求大神解答.重赏~~~ -
东油15227324854…… 原式=[(3x+4)/(x²-1)-2(x+1)/(x²-1)]+(x+2)/(x-1)² =(3x+4-2x-2)/(x²-1)+(x+2)/(x-1)² =(x+2)/(x²-1)+(x+2)/(x-1)² =(x+2)(x-1)/(x+1)(x-1)²+(x+2)(x+1)/(x+1)(x-1)² =(x+2)(x-1+x+1)/(x+1)(x-1)² =2x(x+2)/(x+1)(x-1)² x+4>0,得:x>-4 2x+...
@鄢王2760：初三数学中考化简求值专项训练题 -
东油15227324854…… 1.(3X+2Y)+(4X+3Y)其中X=5,Y+3 原式=3X+2Y+4X+3Y=7X+5Y 当X=5,Y=3时 原式=5*7+(-3)*5+20 2.(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2),其中a=-1,b=1 =5a^2-3b^2+a^2+b^2-5a^2-3b^2 =a^2-5b^2 =(-1)^2-5*1^2 =1-5 =-4 3.2(a^2b+ab^2)-2(a^...
@鄢王2760：先化简,再求值:(1)4(x+1)2 - 2x(2x - 3),其中x= - 3.(2)(x+2)(x - 2) - (x+3)(x - 1),其中x=2. - 作业帮
东油15227324854…… [答案] (1)4(x+1)2-2x(2x-3) =4x2+8x+4-4x2+6x =14x+4, 当x=-3时,原式=14*(-3)+4=-38; (2)(x+2)(x-2)-(x+3)(x-1) =x2-4-x2-2x+3 =-2x-1, 当x=2时,原式=-2*2-1=-5.
@鄢王2760：初三数学化简求值题目,~ -
东油15227324854…… [2/(x+1)+4/(x²-1)]÷x/(x-1) =[(2/(x+1)+4/(x-1)(x+1)]÷x/(x-1) =[2(x-1)/(x+1)(x-1)+4/(x-1)(x+1)]÷x/(x-1) =[2(x-1)+4/(x-1)(x+1)]÷x/(x-1) =[2(x+1)/(x-1)(x+1)]÷x/(x-1) =[2/(x-1)]÷x/(x-1) =[2/(x-1)]*(x-1)/x =2/x 当x=2时 上式=1
@鄢王2760：先化简,再求值:(2a - b)2 - 2a(a - b) - (2a2+b2),其中a=3+1,b=3 - 1. - 作业帮
东油15227324854…… [答案] (2a-b)2-2a(a-b)-(2a2+b2), =4a2-4ab+b2-2a2+2ab-2a2-b2, =-2ab, 当a= 3+1,b= 3-1时, 原式=-2( 3+1)( 3-1)=-4.
@鄢王2760：求初三,十道化简求值题.
东油15227324854…… 3a^2 + ab - 2b^2 = 0即(3a-2b)(a+b)=0即3a-2b=0或a+b=0;故(1)3a-2b=0即b=1.5a时,a/b + b/a + (a^2 + b^2 ) / ab =2/3+3/2+[a^2 +(1.5a)^2 ]/[a*(3/2)a] =13/6+(13/4)*(2/3)=13/3;(2)a+b=0时, a/b + b/a + (a^2 + b^2 ) / ab =2(a^2 + b^2 ) / ab =2[(a+b)^2-2ab]/ab=2(0-2ab)/ab=-2 这个问题求初三,十道化简求值题.,好难啊,辛辛苦苦回答了,给我个满意答案把 http://www.henanlj.com/
@鄢王2760：先化简,后求值:5(m+n)(m - n) - 2(m+n)2 - 3(m - n)2,其中m= - 2,n=15. - 作业帮
东油15227324854…… [答案] 5(m+n)(m-n)-2(m+n)2-3(m-n)2 =5(m2-n2)-2(m2+2mn+n2)-3(m2-2nm+n2) =5m2-5n2-2m2-4mn-2n2-3m2+6nm-3n2 =-10n2+2mn, 把m=-2,n= 1 5代入上式得: 原式=-10n2+2mn=-10*( 1 5)2+2*(-2)*( 1 5)=- 2 5- 4 5=- 6 5.
东油15227324854…… [答案] 例1、化简 (08宁波市) 例2、化简: (08泸州市) = = = = = . 2、乘除型化简 例3、化简: (08年大连市改编) 分析:在解答化简问题时,我们要做到如下几点: 1、当分子、分母是多项式时,先进行分解因式; 2、进行通分; 3、进行约分,化...
@鄢王2760：谁知道有化简求值《整式加减》的题,要有答案的.大概30道左右.thanks! - 作业帮
东油15227324854…… [答案] (一)填空 3.3ab-4ab+8ab-7ab+ab=______. 4.7x-(5x-5y)-y=______. 5.23a3bc2-15ab2c+8abc-24a3bc2-8abc=______. 6.... D.以上答案都不对. (三)化简 70.(4x2-8x+5)-(x3+3x2-6x+2). 72.(0.3x3-x2y+xy2-y3)-(-0.5x3-x2y+0.3xy2). 73.-{2a2b-[3abc-(4ab...
@鄢王2760：初三数学解答题求解先化简再求值:(1+1/x - 1)除以x/x的平方 - 1,其中x= - 4 - 作业帮
东油15227324854…… [答案] [1+1/(x-1)]÷x/(x²-1) =[(x-1)/(x-1)+1/(x-1)]÷x/(x+1)(x-1) =x/(x-1)*(x+1)(x-1)/x =x+1 其中x=-4 原式=-4+1=-3
@鄢王2760：一道初三的化简求值题目,求大神解答.重赏~~~ -
东油15227324854…… 原式=[(3x+4)/(x²-1)-2(x+1)/(x²-1)]+(x+2)/(x-1)² =(3x+4-2x-2)/(x²-1)+(x+2)/(x-1)² =(x+2)/(x²-1)+(x+2)/(x-1)² =(x+2)(x-1)/(x+1)(x-1)²+(x+2)(x+1)/(x+1)(x-1)² =(x+2)(x-1+x+1)/(x+1)(x-1)² =2x(x+2)/(x+1)(x-1)² x+4>0,得:x>-4 2x+...
@鄢王2760：初三数学中考化简求值专项训练题 -
东油15227324854…… 1.(3X+2Y)+(4X+3Y)其中X=5,Y+3 原式=3X+2Y+4X+3Y=7X+5Y 当X=5,Y=3时 原式=5*7+(-3)*5+20 2.(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2),其中a=-1,b=1 =5a^2-3b^2+a^2+b^2-5a^2-3b^2 =a^2-5b^2 =(-1)^2-5*1^2 =1-5 =-4 3.2(a^2b+ab^2)-2(a^...
@鄢王2760：先化简,再求值:(1)4(x+1)2 - 2x(2x - 3),其中x= - 3.(2)(x+2)(x - 2) - (x+3)(x - 1),其中x=2. - 作业帮
东油15227324854…… [答案] (1)4(x+1)2-2x(2x-3) =4x2+8x+4-4x2+6x =14x+4, 当x=-3时,原式=14*(-3)+4=-38; (2)(x+2)(x-2)-(x+3)(x-1) =x2-4-x2-2x+3 =-2x-1, 当x=2时,原式=-2*2-1=-5.
@鄢王2760：初三数学化简求值题目,~ -
东油15227324854…… [2/(x+1)+4/(x²-1)]÷x/(x-1) =[(2/(x+1)+4/(x-1)(x+1)]÷x/(x-1) =[2(x-1)/(x+1)(x-1)+4/(x-1)(x+1)]÷x/(x-1) =[2(x-1)+4/(x-1)(x+1)]÷x/(x-1) =[2(x+1)/(x-1)(x+1)]÷x/(x-1) =[2/(x-1)]÷x/(x-1) =[2/(x-1)]*(x-1)/x =2/x 当x=2时 上式=1
@鄢王2760：先化简,再求值:(2a - b)2 - 2a(a - b) - (2a2+b2),其中a=3+1,b=3 - 1. - 作业帮
东油15227324854…… [答案] (2a-b)2-2a(a-b)-(2a2+b2), =4a2-4ab+b2-2a2+2ab-2a2-b2, =-2ab, 当a= 3+1,b= 3-1时, 原式=-2( 3+1)( 3-1)=-4.
@鄢王2760：求初三,十道化简求值题.
东油15227324854…… 3a^2 + ab - 2b^2 = 0即(3a-2b)(a+b)=0即3a-2b=0或a+b=0;故(1)3a-2b=0即b=1.5a时,a/b + b/a + (a^2 + b^2 ) / ab =2/3+3/2+[a^2 +(1.5a)^2 ]/[a*(3/2)a] =13/6+(13/4)*(2/3)=13/3;(2)a+b=0时, a/b + b/a + (a^2 + b^2 ) / ab =2(a^2 + b^2 ) / ab =2[(a+b)^2-2ab]/ab=2(0-2ab)/ab=-2 这个问题求初三,十道化简求值题.,好难啊,辛辛苦苦回答了,给我个满意答案把 http://www.henanlj.com/
@鄢王2760：先化简,后求值:5(m+n)(m - n) - 2(m+n)2 - 3(m - n)2,其中m= - 2,n=15. - 作业帮
东油15227324854…… [答案] 5(m+n)(m-n)-2(m+n)2-3(m-n)2 =5(m2-n2)-2(m2+2mn+n2)-3(m2-2nm+n2) =5m2-5n2-2m2-4mn-2n2-3m2+6nm-3n2 =-10n2+2mn, 把m=-2,n= 1 5代入上式得: 原式=-10n2+2mn=-10*( 1 5)2+2*(-2)*( 1 5)=- 2 5- 4 5=- 6 5.
