若(a^n)2=4,求(-2a^3N)2-(0.5a^2n)3的值

问题描述:

若(a^n)2=4,求(-2a^3N)2-(0.5a^2n)3的值

∵(a^n)^2=a^2n=4,
∴原式=4a^6n-1/8a^6n
=31/8a^6n
=31/8*(a^2n)^3
=31/8×64
=248.