已知a=3/4,b=-2/3,求分式3a^2-ab/9a^2-6ab+b^2的值.

问题描述:

已知a=3/4,b=-2/3,求分式3a^2-ab/9a^2-6ab+b^2的值.

原式=a(3a-b)/(3a-b)²
=a/(3a-b)
=(3/4)/(9/4+2/3)
=9/35