Question

幂函数f(x)的图像过点(4,0.5) f(8)是?

Answer 1

设幂函数 f(x) = a^x .

已知,f(x)的图像过点(4,0.5) ,可得：0.5 = a^4 ,

所以,f(8) = a^8 = (a^4)^2 = 0.5^2 = 0.25 .