2的2n+1次方+4的n次方=48
2的2n+1次方+2的2n次方=48
2×2的2n次方+2的2n次方=48
3×2的2n次方=48
2的2n次=16=2的4次方
2n=4
n=2合并同类项2×2的2n次方+2的2n次方=48（2+1）×2的2n次方=483×2的2n次方=482的2n次=16=2的4次方2n=4n=2