Question

若2乘以8的n次方乘以16的n次方=2的22次方,则n的值是多少

Answer 1

2乘以8的n次方乘以16的n次方=2的22次方

2*8^n*16^n=2^22

2*(2^3)^n*(2^4)^n=2^22

2*2^(3n)*2^(4n)=2^22

2^(1+3n+4n)=2^22

则

1+3n+4n=22

7n=21

n=3