Re: [中學] 對數
※ 引述《m87917739 (mel)》之銘言：
: 第一題
: http://imgur.com/a/jZ5cz
log(5x) * log(x/6) * log(x) + 4 = log(x) + log(3)
u = log(x)
[u + log(5)][u - log6]u - u + (log(3) + 4) = 0
u^3 - (log(6/5))u^2 - (1 + log(5)log(6))u + (log(3) + 4) = 0
=> 求解u => x = 10^u
: 麻煩大家幫忙！
: 完全忘記對數怎麼計算了....
: 謝謝!!!!
--
※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 111.249.193.168
※ 文章網址: https://www.ptt.cc/bbs/Math/M.1484243181.A.D68.html
→
01/13 16:35, , 1F
01/13 16:35, 1F
討論串 (同標題文章)
