2×8的m次方×16的m次方等于2的22次方,问m等于几?

问题描述:

2×8的m次方×16的m次方等于2的22次方,问m等于几?

2×8^m×16^m
=2×(2³)^m×(2^4)^m
=2×2^(3m)×2^(4m)
=2^(1+3m+4m)
=2^(7m+1)
=2^22
∴7m+1=22
7m=22-1
7m=21
m=3