已知a+b=2,ab=3,1/2a^3b
问题描述:
已知a+b=2,ab=3,1/2a^3b
已知a+b=2,ab=3,求1/2a^3b+a^2b^2+1/2ab^3的值.
答
1/2a^3b+a^2b^2+1/2ab^3
=1/2ab(a²+2ab+b²)
=1/2×3×(a+b)²
=3/2×2²
=6