推 rey9810 : 謝謝！ 12/14 00:09
※ 引述《rey9810 (RaY)》之銘言：
: 卡了3題 第二題好像有3次公式的影子？
: 感謝幫忙！！！
: http://i.imgur.com/BUuqywO.jpg
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: Sent from JPTT on my LGE LG-H788.
1.
(3/2)log3 + 3log2 - (3/2)log10
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2log2 + log3 - 1
= 3/2
2.
(log2)^3 + (log5)^3 + log5 * log8
= (log2)^3 + (log5)^3 + 3log5 * log2
= (log2)^3 + (1 - log2)^3 + 3(1 - log2) * log2
= 1 - 3(log2) + 3(log2)^2 + 3log2 - 3(log2)^2
= 1
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