Question

2道分式计算题1.若(1/a)+(1/b)=1/(a+b),求(b/a)+(a/b)值.2.已知(x+3)/(x+2)=

Answer 1

1.(1/a)+(1/b)=1/(a+b)得 (b+a)/(ab)= 1/(a+b)得(a+b)^2=ab 则(b/a)+(a/b)=((a+b)^2-2ab)/(ab)=-1