Question

已知2的2n+3次方减2的2n+1次方=192,求n的值

Answer 1

解

2^(2n+3)-2^(2n+1)=192

2^(2n+1)(4-1)=192

2^(2n+1)=192÷3

2^(2n+1)=64=2^6

∴2n+1=6

∴n=5/2