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若x-2y-2=0,求3^x/9^y
人气:226 ℃ 时间:2020-10-01 21:25:23
解答
x-2y-2=0
x=2y+2
3^x/9^y
=3^(2y+2)/9^y
=9*9^y/9^y
=9=9*9^y/9^y 为何为9x93^(2y+2)=3^(3y)*3^2=9^y*9
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