Question

化简：[x+1 -(15/x-1)] * (x-4/x-1)

Answer 1

*应该是÷

原式=[(x+1)(x-1)-15]/(x-1)*(x-1)/(x-4)

=(x²-16)/(x-1)*(x-1)/(x-4)

=(x+4)(x-4)/(x-1)*(x-1)/(x-4)

=x+4