以y表示x..
a)1/2 logx=2+logy
b)log(x-2y)=3
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form 4 maths...
2007-08-27 6:06 am
回答 (2)
2007-08-27 6:09 am
✔ 最佳答案
a)1/2 logx=2+logylog(x^1/2) = log100+logy
log(x^1/2)=log 100y
x^1/2 = 100y
x=(100y)^2
x=10000y^2
b)log(x-2y)=3
log(x-2y)=log10^3 = log 1000
x-2y=1000
x=1000+2y
參考: me
2007-08-27 6:13 am
a) log x ^(1/2) = log2y
2y = x^(1/2)
y = x^(1/2)/2
b) log(x-2y) = 3
x-2y = 10^3
y = x/2 - 500
2007-08-26 22:16:58 補充：
a) log x^(1/2) = log 100 + log y = log100y x^(1/2) = 100 y x = 10000 y^2b) x - 2y = 10^3 x = 2y + 1000
2y = x^(1/2)
y = x^(1/2)/2
b) log(x-2y) = 3
x-2y = 10^3
y = x/2 - 500
2007-08-26 22:16:58 補充：
a) log x^(1/2) = log 100 + log y = log100y x^(1/2) = 100 y x = 10000 y^2b) x - 2y = 10^3 x = 2y + 1000
收錄日期: 2021-04-13 18:12:18
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