$log_{\frac{1}{2}}9$, $log_{\frac{1}{4}}\frac{1}{3}$, $log_{\frac{1}{8}}3$ を値の小さい順に並べる。代数学対数対数関数大小比較2025/7/311. 問題の内容log129log_{\frac{1}{2}}9log219, log1413log_{\frac{1}{4}}\frac{1}{3}log4131, log183log_{\frac{1}{8}}3log813 を値の小さい順に並べる。2. 解き方の手順まず、それぞれの対数の値を計算します。log129=log9log12=log32log2−1=2log3−log2=−2log3log2log_{\frac{1}{2}}9 = \frac{log 9}{log \frac{1}{2}} = \frac{log 3^2}{log 2^{-1}} = \frac{2 log 3}{-log 2} = -2 \frac{log 3}{log 2}log219=log21log9=log2−1log32=−log22log3=−2log2log3log1413=log13log14=log3−1log4−1=−log3−log4=log3log4=log3log22=log32log2=12log3log2log_{\frac{1}{4}}\frac{1}{3} = \frac{log \frac{1}{3}}{log \frac{1}{4}} = \frac{log 3^{-1}}{log 4^{-1}} = \frac{-log 3}{-log 4} = \frac{log 3}{log 4} = \frac{log 3}{log 2^2} = \frac{log 3}{2 log 2} = \frac{1}{2} \frac{log 3}{log 2}log4131=log41log31=log4−1log3−1=−log4−log3=log4log3=log22log3=2log2log3=21log2log3log183=log3log18=log3log8−1=log3−log8=log3−log23=log3−3log2=−13log3log2log_{\frac{1}{8}}3 = \frac{log 3}{log \frac{1}{8}} = \frac{log 3}{log 8^{-1}} = \frac{log 3}{-log 8} = \frac{log 3}{-log 2^3} = \frac{log 3}{-3 log 2} = -\frac{1}{3} \frac{log 3}{log 2}log813=log81log3=log8−1log3=−log8log3=−log23log3=−3log2log3=−31log2log3ここで、log3log2\frac{log 3}{log 2}log2log3 は正の値であることに注意します。それぞれの係数を比較すると、−2<−13<12-2 < -\frac{1}{3} < \frac{1}{2}−2<−31<21したがって、log129<log183<log1413log_{\frac{1}{2}}9 < log_{\frac{1}{8}}3 < log_{\frac{1}{4}}\frac{1}{3}log219<log813<log41313. 最終的な答えlog129log_{\frac{1}{2}}9log219, log183log_{\frac{1}{8}}3log813, log1413log_{\frac{1}{4}}\frac{1}{3}log4131