Re: [中學] 指數對數
※ 引述《susiseptem (..)》之銘言：
: http://imgur.com/a/3MX4K
: 11題的部分 麻煩各位前輩了
u = x^(log2)
log(u) = log(2) * log(x)
2^log(x) = 2^[log(u) / log(2)]
= u
所以u = x^(log2) = 2^log(x)
u^2 - 3u - 2u + 4 = 0
=> u = 4 or 1
=> log(x) = log_2 (u)
= 2 or 0
=> x = 100 or 1
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