Question

先化简再求值x^2-1分之x*x^2分之x^2+x其中x=2

要过程 急
要过程

Answer 1

X/(X^2-1) *(X^2+X)/X^2
=X*(X^2+X)/(X^2-1)*X^2
=X*X(X+1)/(X+1)(X-1)*X*X
=1/(X-1)

1/(2-1)=1