1÷2x-7=9x-2÷6

等于37因为：【】都是一样的数字的话那他们就可以合并同类项：[]{10+1}*5=1980所以算出为37~

(x+1-1/1-x)÷(x-x²/x-1)=[(x+1)+1/(x-1)]×[-(x-1)/x(x-1)]=(x²-1+1)/(x-1)×(-1/x)=-x/(x-1)(x-4/

A={x|x^2-2x-3<3(1-x)}={x|x^2+x-6<0}={x|-3<x<2}B={x|9-x^2>6-2x}={x|x^2-2x-3<0}={x|-

|x-1|+|x-10|表示数轴上x到1的距离+x到10的距离.显然最小值是9,此时x只要在1到10之间就好.类似的,|x-2|+|x-9|的最小值是7,此时x在2到9之间就好.|x-3|+|x-8|

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+3+4+5+6+7+8+9+10+11)=1980,X66=1980等于30

x(1+2+...+9)=x(9-8-7-...-1)x=0记得采纳啊

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-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)]/

/>(4X+2)/X+【4(X-5)-2】/(X-5)=【(X-4)-2】/(X-4)+【7(X+1)+2】/(X+1)4+2/X+4-2/(X-5)=1-2/(X-4)+7+2/(X+1)8+2/X

(x^2+7x+10)/(x^2+6x+5)×(x^3+1)/(x^2+4x+4)÷(x^2-x+1)/(x+2)=(x+2)(x+5)/(x+1)(x+5)*(x+1)(x^2-x+1)/(x+2)

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/

解1：原式=x(x-1)/(x+1)*(x+1)/x=x-1解2：原式=(x+3)^2/(x+3)(x-3)*(x-3)/(x+2)=(x+3)/(x-3)*(x-3)/(x+2)=(x+3)/(x+

原式化简：{（x-3)(x-2)/(x-3)(x-4)}²÷{(x+1)(x+2)/(x-4)(x+2)}²{(x-2)/(x-4)}²÷{(x+1)/(x-4)}

把x2+7x+10化成(x+2）（x+5）同理就可以约分了最后约分成最简,把想=9/2代入,就可以啦

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-2)/(x+3)(x-3)×(x²+2x-3)/(x-2)²×(x+3)/(x+1)=(x-2)/(x+3)(x-3)×(x-3)(x+1)/(x-2)²×(x+