若(32/243)^n/(4/9)^n=3又3/8,求n的值 256^b=2^16,求b的值
问题描述:
若(32/243)^n/(4/9)^n=3又3/8,求n的值 256^b=2^16,求b的值
答
32/243 = (2/3)^5
(32/243)^n/(4/9)^n = (2/3)^5n / (2/3)^2n = (2/3)^3n = (3/2)^3 = (2/3)^(-3)
所以3n = -3
n=-1
256^b=(2^8)^b = 2^8b = 2^16
所以8b=16
b=2