已知a/b=3/5,求下列算式的值.1.a-b/b 2.2a+b/2a-b

Question

已知a/b=3/5,求下列算式的值.1.a-b/b 2.2a+b/2a-b

Answer 1

a/b=3/5a=3/5ba-b/b=(3/5b-b)/b=(-2/5b)/b=-2/5(2a+b)/(2a-b)=(3/5bx2+b)/(3/5bx2-b)=(11/5b)/(1/5b)=11