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1.如果2*8^n*16^n=2^22.求n的值?2.(x-y)^4(x-y)-2(x-y)^2(y-x)^3=3.已知8^n=5,4^m=7,求2^4m+6n的值?

题目详情
1.如果2*8^n*16^n=2^22.求n的值?
2.(x-y)^4(x-y)-2(x-y)^2(y-x)^3 =
3.已知8^n=5,4^m=7,求2^4m+6n的值?
▼优质解答
答案和解析
2*2^3n*2^4n=2^7n+1=2^22 7n+1=22 n=3
(x-y)^5-2(y-x)^2*(y-x)^2(y-x)^3=-(y-x)^5-2(y-x)^5=-3(y-x)^5
2^3n=5 (2^3n)^2=2^6n=25
2^2m=7 (2^2m)^2=2^4m=49
2^4m+6n=2^6n*2^4m=25*49=1225