已知a^m=-2,a^n=3,求a^3m+2n的值.若x^m*x^2m=-2,求^9m的值.
问题描述:
已知a^m=-2,a^n=3,求a^3m+2n的值.若x^m*x^2m=-2,求^9m的值.
答
a^(3m+2n)=a^3m+a^2n=(-2)^3·3^2=-72. 第二个问题没看懂 补充:x^m*x^2m=-2得x^3m=-2. x^9m=(x^3m)^3=(-2)^3=-8 补充:快点采纳我我就去睡觉了= = 追问:做对了