Question

1.当x____时,1/x+1有意义 化简：1.（3x/(x+2)-x/x-2)+2x/x²-4 2.（a/b-b/a）÷a+b/a

3.（x-1/(x+1)+2x/x²-1）÷1/x²-1
4.（2x-3/（x）-1）÷x²-9/x

Answer 1

1、≠-1

1、3x(x-2)/(x²-4）-x(x+2)/(x²-4)+2x/(x²-4)
=(3x²-6x-x²-2x+2x)/(x²-4)
=(2x²-6x)/(x²-4)

2、(a²-b²)/ab×a/(a+b)
=(a-b)/b

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

4、(2x-3-x)/x×x/(x+3)(x-3)
=(x-3)/x×x/(x+3)(x-3)
=1/(x+3)