X的二次方+2x+1分之x的平方-1除1+x分之x-1

问题描述:

X的二次方+2x+1分之x的平方-1除1+x分之x-1

(x²-1)/(x²+2x+1)-1÷(x-1)/(x+1)=(x+1)(x-1)/(x+1)²-(x+1)/(x-1)=(x-1)/(x+1)-(x+1)/(x-1)={(x-1)²-(x+1)²}/(x+1)(x-1)=-4x/(x²-1)