2.若m等于它的倒数,则分式m-2/m^2-4÷m^2-3m/m-3的值为 A.-1 B.3 C.-1或3 D.-4/18.已知x-3y=0,求x^2-2xy+y^2/2x+y乘（x-y)的值.4.已知a/1+b/1=2/1,则a+b/ab的值是 A.2/1 B.-2/1 C.2 D.-25.式子x+2/x+1÷2x+3/x-2有意义,则x应满足

2.若m等于它的倒数,则分式m-2/m^2-4÷m^2-3m/m-3的值为 A.-1 B.3 C.-1或3 D.-4/18.已知x-3y=0,求x^2-2xy+y^2/2x+y乘（x-y)的值.4.已知a/1+b/1=2/1,则a+b/ab的值是 A.2/1 B.-2/1 C.2 D.-25.式子x+2/x+1÷2x+3/x-2有意义,则x应满足
2.若m等于它的倒数,则分式m-2/m^2-4÷m^2-3m/m-3的值为 A.-1 B.3 C.-1或3 D.-4/1
8.已知x-3y=0,求x^2-2xy+y^2/2x+y乘（x-y)的值.
4.已知a/1+b/1=2/1,则a+b/ab的值是 A.2/1 B.-2/1 C.2 D.-2
5.式子x+2/x+1÷2x+3/x-2有意义,则x应满足的条件是 A.x不等于±2且x不等于-2/3
B.x不等于-2且x不等于-2/3 C.x不等于2且x不等于-2/3 D.以上都不对
15.（2)1-a+2b/a-b乘a^2-b^2/a^2+4ab+4b^2
16.先化简,再求值：（x-1/1 +1)除x^2-1/x,其中x=2

2.若m等于它的倒数,则分式m-2/m^2-4÷m^2-3m/m-3的值为 A.-1 B.3 C.-1或3 D.-4/18.已知x-3y=0,求x^2-2xy+y^2/2x+y乘（x-y)的值.4.已知a/1+b/1=2/1,则a+b/ab的值是 A.2/1 B.-2/1 C.2 D.-25.式子x+2/x+1÷2x+3/x-2有意义,则x应满足
c