已知2^m=3,4^n=2求2^2m-4n+1 要对的啊 过程最好全一点

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已知2^m=3,4^n=2求2^2m-4n+1要对的啊过程最好全一点已知2^m=3,4^n=2求2^2m-4n+1要对的啊过程最好全一点已知2^m=3,4^n=2求2^2m-4n+1要对的啊过程最好全

已知2^m=3,4^n=2求2^2m-4n+1 要对的啊 过程最好全一点
已知2^m=3,4^n=2求2^2m-4n+1 要对的啊 过程最好全一点

已知2^m=3,4^n=2求2^2m-4n+1 要对的啊 过程最好全一点
由4^n=2可得n=1/2,所以
2^2m-4n+1 =(2^m)(2^m)-4n+1=3X3-4X1/2+1=8
如果是题目表达不明确,(2m-4n+1) 整个都是指数,则:
2^(2m-4n+1) = (2^2m) / 2^4n X 2 = 2(2^m)(2^m) / (((2^2)^n)^2) = 2X3X3/((4^n)^2) = 18/4 =4.5

4^n=2
2^2n=2
n=1/2
2^2m-4n+1=(2^m)^2-4×1/2+1
=3^2-2+1
=8

4^n=2,则n = log(4) 2 = log(4) 4^(1/2) =1/2
所以原式= (2^m)^2 -4 * 1/2 +1 = 3²-2+1 =8

2^m=3 那么2^2m=(2^m)²=9
4^n=2 那么n=1/2
所以2^2m-4n+1
=9-4*1/2+1
=9-2+1
=8