求一道数学题解法,

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求一道数学题解法,
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求一道数学题解法,
求一道数学题解法,

求一道数学题解法,
原题(3/2)^x=4/9;2^y=1/3²,求1/(x+y)².
  改成 “(3/2)^x=4/9;2^y=1/2³,求1/(x+y)².”初一的学生就能做了.
(3/2)^x=(2/3)²=(3/2)⁻²,故x=-2;
  2^y=1/2³,y=-3.
  于是,1/(x+y)²=1/25.

(log20.25(1.5))^2

若(3/2)^x=4/9;2^y=1/3²;求1/(x+y)²
(3/2)^x=(2/3)²=(3/2)⁻²,故x=-2;
2^y=1/9,那么y=log₂(1/9)=2log₂(1/3)=-2log₂3;
故1/(x+y)²=1/(-2-2log₂3)²=1/[4(1+log₂3)²]