如果a/b=2/3,且a不等于2,那么a-b+1/a+b-5=

Question

如果a/b=2/3,且a不等于2,那么a-b+1/a+b-5=

Answer 1

a/b=2/3
设a=2k；b=3k
a-b+1/a+b-5
=(2k-3k+1)/(2k+3k-5)
=(1-k)/[5(k-1)]
=-1/5