若5^m=2 25^n=3,求5^2m-4n+3的值~

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若5^m=225^n=3,求5^2m-4n+3的值~若5^m=225^n=3,求5^2m-4n+3的值~若5^m=225^n=3,求5^2m-4n+3的值~5^2m-4n+3=(5^m)^2÷(5^2

若5^m=2 25^n=3,求5^2m-4n+3的值~
若5^m=2 25^n=3,求5^2m-4n+3的值~

若5^m=2 25^n=3,求5^2m-4n+3的值~
5^2m-4n+3
=(5^m)^2÷(5^2)^2n×5^3
=(5^m)^2÷(25^n)^2×5^3
=2^2÷3^2×125
=500/9

5^m=2, 5^(2m)=2^2=4
25^n=3 得:5^(2n)=3, 所以:5^(4n)=9
5^2m-4n+3=5^2mx5^3/5^(4n)=4x125/9=500/9