Question

用两种方法计算

Answer 1

（1）（3x/x-2 － x/x+2）* x的平方-4/x

=[3x（x+2)-x(x-2)](x^2-4)/(x^-4)x

=(3x^2+6x-x^2+2x)/x

=2x+8

(2)[3x(x^2-4)/(x-2) － x(x^2-4)/(x+2）]/x

=x[3(x^2-4)/(x-2) －x(x^2-4)/(x+2)]/x

=3(x+2)-(x-2)

=2x+8