Question

2的2n+1次方加上4的n次方等于48 ,求n的值.

Answer 1

2的2n+1次方加上4的n次方

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

=2*2^2n+2^2n

=3*2^2n

=48

所以2^2n=16

2n=4

n=2