Question

已知2的a次方=10,2的4b次方=5,求4的a-4b的次方+2的3a-8b的值

Answer 1

2^a=10 2^4b=5 所以 2*2^4b=10 2^4b+1=10 a=4b+1

4^(a-4b)+2^(3a-8b)

=4+2^(12b+3-8b)

=4+2^4b*2^3

=4+40

=44