答案:D
解析:
If x>0 and y>0, and if 3^(2x) = 27^(2y), then rewriting 27 as 3^3 gives 3^(2x) = 27^(2y) = (3^3)^(2y) = 3^(3(2y)). It follows that 3^(2x) = 3^(3(2y)) = 3^(6y), and so 2x = 6y. This last equation is equivalent to x = 3y.
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答案:D
解析:
If x>0 and y>0, and if 3^(2x) = 27^(2y), then rewriting 27 as 3^3 gives 3^(2x) = 27^(2y) = (3^3)^(2y) = 3^(3(2y)). It follows that 3^(2x) = 3^(3(2y)) = 3^(6y), and so 2x = 6y. This last equation is equivalent to x = 3y.