SOLVE 14=2^X
Without using a calculator , simplify log5(0.04)
個5 係細D 個個... Log (0.04)
5
log 數學白痴問題
2008-06-04 9:52 pm
回答 (2)
2008-06-04 11:18 pm
14=2^x
log14=xlog2
x=(log14)/(log2)
x=3.80735
(log0.04)^5
=5log0.04
=5(log4/100)
=5(log4-2)
=5log4-10
###i think this is the simplest, cause there is no decimal
2008-06-04 15:23:05 補充：
(2) MAYBE this one
(log0.04)^5
=5log0.04
=5(log1/25)
=5(0-2log5)
=-10log5
i dont which one is the answer
log14=xlog2
x=(log14)/(log2)
x=3.80735
(log0.04)^5
=5log0.04
=5(log4/100)
=5(log4-2)
=5log4-10
###i think this is the simplest, cause there is no decimal
2008-06-04 15:23:05 補充：
(2) MAYBE this one
(log0.04)^5
=5log0.04
=5(log1/25)
=5(0-2log5)
=-10log5
i dont which one is the answer
參考: me
2008-06-04 10:10 pm
1.) 1 + log2 (7) = X
2.) log5 (1/25)
2008-06-04 14:37:59 補充：
2.) -2
2008-06-04 15:40:23 補充：
補充2.) log (a/b) = log (a) - log (b)
所以 log5 (1/5^2) = log5 (1) - log5 (5^2) = 0 - 2log 5 (5) = -2 (1) = -2
2008-06-04 15:45:04 補充：
補充1.) 2^X = 14
2^X = (2)(7)
(2^X)/2 = 7
(2^(X-1))=7
Take Log to the power of 2
log2 (7) = X-1
X = 1 + log2 (7)
2.) log5 (1/25)
2008-06-04 14:37:59 補充：
2.) -2
2008-06-04 15:40:23 補充：
補充2.) log (a/b) = log (a) - log (b)
所以 log5 (1/5^2) = log5 (1) - log5 (5^2) = 0 - 2log 5 (5) = -2 (1) = -2
2008-06-04 15:45:04 補充：
補充1.) 2^X = 14
2^X = (2)(7)
(2^X)/2 = 7
(2^(X-1))=7
Take Log to the power of 2
log2 (7) = X-1
X = 1 + log2 (7)
參考: 個人意見，請自己計
收錄日期: 2021-04-25 22:22:30
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