2的2n+1方+4的n次方=48

下面以 2^(2n + 1) 表示 2的2n+1次方,依此类推.
2^(2n + 1) + 4^n = 48
2·2^(2n) + 4^n = 48
2·4^n + 4^n = 48
3·4^n = 48
4^n = 16
n = 2

2的2n+1方+4的n次方=48
2^(2n+1)+4^n=48
2×2^2n+2^2n=3×2^n=48
2^n=16,n=4