1 2*(6-x)2x=8

(x+3)/(x+2)+(x+9)/(x+8)=(x+5)/(x+4)+(x+7)/(x+6)1+(x+5)/(x+2)(x+8)=1+(x+5)/(x+4)(x+6)x=-5再问：第二步那个1是怎么

设a=(x-1)(x-2)(x-3)(x-4)(x-5)(x-6)(x-7)(x-8)(x-9)那么y=a*(x-10);那么y^=a^*(x-10)+a*(x-10)^=a^*(x-10)+a那么y

1）（x-3）/（x-2）-（x-5）/（x-4）=（x-7）/（x-6）-（x-9）/（x-8）化简得【（x-3）（x-4）-（x-5）/（x-2）】/【（x-2）（x-4)】=【（x-7）（x-8

 再问：额、不懂再答： 再答：后面的看做一个整体再问：好的吧、谢谢大神再答：回来的话，请采纳再问：啊、突然明白了呢。。。

1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550120x=550x=55/12=4.583

x(1+2+...+9)=x(9-8-7-...-1)x=0记得采纳啊

(X+2)/(X+1)-(X+4)/(X+3)=(X+6)/(X+5)-(X+8)/(X+7)(X+1+1)/(X+1)-(X+3+1)/(X+3)=(X+5+1)/(X+5)-(X+7+1)/(X+

x+x^2+x^3+x^4+x^5+x^6+x^7+x^8=（x+x^2+x^3+x^4）+（x^5+x^6+x^7+x^8）=x（1+x+x^2+x^3）+x^5（1+x+x^2+x^3）=（x+x

x/(x-2)+(x-9)/(x-7)=(x+1)/(x-1)+(x-8)/(x-6)1+2/(x-2)+1-2/(x-7)=1+2/(x-1)+1-2/(x-6)1/(x-2)-1/(x-7)=1/

5x/(x²+x-6)+(2x-5)/(x²-x-12)=(7x-10)/(x²-6x+8)5x/(x-2)(x+3)+(2x-5)/(x+3)(x-4)=(7x-10)

(5-2x)/(x^2-x-12)=5x/(x^2+x-6)+(10-7x)/(x^2-6x+8)(5-2x)/(x-4)(x+3)=5x/(x+3)(x-2)+(10-7x)/(x-2)(x-4)分

(x-9)/(x-7)-(x+1)/(x-1)=(x-8)/(x-6)-x/(x-2)[(x-9)(x-1)-(x+1)(x-7)]/[(x-7)(x-1)]=[(x-8)(x-2)-x(x-6)]/

1+x+x^2+x^3=0x+x^2+x^3+x^4+x^5+x^6+x^7+x^8=(x+x^2+x^3+x^4)+(x^5+x^6+x^7+x^8)=x(1+x+x^2+x^3)+x^5(1+x+

主要是考察因式分解这方面的技能啊![(2x²-5x+2)/(6x²+13x+6)]*[(6x²-5x-6)/(6x²-17x+10)]*[(12x²+

设x1=4-√3,x2=4+√3,是方程X^2-8X+13=0的两根所以X1^2-8X1+15=2X^4-6X^3-2X^2+18X+23=(X+1)^2*(X^2-8X+13)+10=10所以原式=

x/(x-2)+(x-9)/(x-7)=(x+1)/(x-1)+(x-8)/(x-6)1+2/(x-2)+1-2/(x-7)=1+2/(x-1)+1-2/(x-6)1/(x-2)-1/(x-7)=1/

x-o.8x=6X=3012x-8x=4.8X=1.23x-8=16X=8x-0.7x=3.6X=127.5x-2x这题没有=

60X+15X+10X+6X=12091X=120X=120/91

5x/(x²+x-6)+(2x-5)/(x²-x-12)=(7x-10)/(x²-6x+8)5x/[(x+3)(x-2)]+(2x-5)/[(x-4)(x+3)]=(7x

=x^2+10x-24+x^2+15x+56-x^2+5x+50=x^2+30x+82=4+60+82=146其实,不化简,直接代入=14*0+9*10+7*8=0+90+56=146也很简单