百度作业网5 x²+11x-708
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/31 09:12:19
这是两道题吗?1、两边同时乘(x-1)(x-2)(x-3）答案是x1=-1,x2=22、分母因式分解分别为(x-7)(2x+3)和(x-5)(x-7)然后同时乘(x-5)(x-7)(2x+3)答案是x
x/(2x^2-11x-21)=(x+7)/(x^2-12x+35)x/(2x+3)(x-7)=(x+7)/(x-5)(x-7)x/(2x+3)=(x+7)/(x-5)x(x-5)=(x+7)(2x+
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550120x=550x=55/12=4.583
x²+2x=4x²+2x+1=4+1(x+1)²=5x+1=±√5x=-1-√5,x=-1+√5
【解法一】【解法二】5x(x+7)(x+4)=5x(x^2+11X)5x(x²+11x+28)-5x(x²+11x)=05x^3+55x^2+140x=5x^3+55x^25x(x
6x^3+7x^2-13x+11＝6x^3+3x^2-15x+4x^2+2x-10+21＝3x（2x*x+x-5）+2（2x*x+x-5）+21＝3x*0+2*0+21＝21
5x(x+7)(x+4)=5x(x^2+11X)5x^3+55x^2+140x=5x^3+55x^2140x=0x=0
x(2x-3)+3x+3x(x-2)=5x(x-4)+112x²-3x+3x+3x²-6x=5x²-20x+115x²-6x=5x²-20x+115x
[1/(x-1)(x+2)]+[1/(x+2)(x+5)]+[1/(x+5)(x+8)]+[1/(x+8)(x+11)]=(1/3x-3)-1/24(1/3)[1/(x-1)-1/(x+11)]=1/
（2013+2012）X
解题思路：先化简代数式，再把x²-5x=14代入进行计算解题过程：0最终答案：略
原式=[x(x-3)/(x-3)²][(x-5)(x-6)/x(x-5)]-1=[x/(x-3)][(x-6)/x]-1=(x-6)/(x-3)-1=(x-6-x+3)/(x-3)=-3/(
x-1/11x等于152-x-510x/11=147-x21x/11=147x=147×11/21x=77
看三个分母的因式可以知道：首先,每个提出一个常数,把分子化成简单的常数,即化为：1+1/(x^2+6x+9)+1-2/(x^2-9)+2-1/(x^2+4x+3)接着,每个因式分母提出（x+3）,即为
13x-8x-20=2x+223x=42x=14
再问：请给详细过程。再答：
9x-12x+5x=-3x+5x=2x3x-5x-2+5x+8=-2x+5x-2+8=3x+63x+5+2x+3-7-11x=3x+2x-11x+5+3-7=5x-11x+8-7=-6x+1
#includesintjiesheng(intn)//用于计算阶乘如：3!{if(n=1)rerunn;returnn*hh(n-1)}doubledigui(intn,intx)//用以计算y=x
5x²-11x-21=05x²-11x=215[x²-11x/5+(11/10)²]=21+5×(11/10)²(x-11/10)²=541