若3^x=6,9^y=2,求3^2x-4y+2
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![若3^x=6,9^y=2,求3^2x-4y+2](/uploads/image/z/1614110-14-0.jpg?t=%E8%8B%A53%5Ex%3D6%2C9%5Ey%3D2%2C%E6%B1%823%5E2x-4y%2B2)
若3^x=6,9^y=2,求3^2x-4y+2
若3^x=6,9^y=2,求3^2x-4y+2
若3^x=6,9^y=2,求3^2x-4y+2
3^2x=(3^x)^2=6^2=36
3^-4y=1/3^4y=1/9^2y=1/(9^y)^2=1/4
3^2x-4y+2
=36x1/4x9
=81
3^(2x-4y+2)
=(3^x)^2*(3^y)^(-4)*9
=(3^x)^2*(9^y)^(-2)*9
=36*(1/4)*9
=81