与えられた数式の値を計算します。数式は以下の通りです。 $\log_2 10 \cdot \log_5 10 - (\log_2 5 + \log_5 2)$解析学対数底の変換公式計算2025/6/101. 問題の内容与えられた数式の値を計算します。数式は以下の通りです。log210⋅log510−(log25+log52)\log_2 10 \cdot \log_5 10 - (\log_2 5 + \log_5 2)log210⋅log510−(log25+log52)2. 解き方の手順まず、底の変換公式を利用します。底の変換公式は logab=logcblogca\log_a b = \frac{\log_c b}{\log_c a}logab=logcalogcb です。ここでは、底を10に変換します。log210=log1010log102=1log102\log_2 10 = \frac{\log_{10} 10}{\log_{10} 2} = \frac{1}{\log_{10} 2}log210=log102log1010=log1021log510=log1010log105=1log105\log_5 10 = \frac{\log_{10} 10}{\log_{10} 5} = \frac{1}{\log_{10} 5}log510=log105log1010=log1051log25=log105log102\log_2 5 = \frac{\log_{10} 5}{\log_{10} 2}log25=log102log105log52=log102log105\log_5 2 = \frac{\log_{10} 2}{\log_{10} 5}log52=log105log102与えられた数式に代入します。1log102⋅1log105−(log105log102+log102log105)\frac{1}{\log_{10} 2} \cdot \frac{1}{\log_{10} 5} - (\frac{\log_{10} 5}{\log_{10} 2} + \frac{\log_{10} 2}{\log_{10} 5})log1021⋅log1051−(log102log105+log105log102)1log102⋅log105−((log105)2+(log102)2log102⋅log105)\frac{1}{\log_{10} 2 \cdot \log_{10} 5} - (\frac{(\log_{10} 5)^2 + (\log_{10} 2)^2}{\log_{10} 2 \cdot \log_{10} 5})log102⋅log1051−(log102⋅log105(log105)2+(log102)2)1−((log105)2+(log102)2)log102⋅log105\frac{1 - ((\log_{10} 5)^2 + (\log_{10} 2)^2)}{\log_{10} 2 \cdot \log_{10} 5}log102⋅log1051−((log105)2+(log102)2)ここで、log105=log10(10/2)=log1010−log102=1−log102\log_{10} 5 = \log_{10} (10/2) = \log_{10} 10 - \log_{10} 2 = 1 - \log_{10} 2log105=log10(10/2)=log1010−log102=1−log102 を利用します。1−((1−log102)2+(log102)2)log102⋅(1−log102)\frac{1 - ((1 - \log_{10} 2)^2 + (\log_{10} 2)^2)}{\log_{10} 2 \cdot (1 - \log_{10} 2)}log102⋅(1−log102)1−((1−log102)2+(log102)2)1−(1−2log102+(log102)2+(log102)2)log102−(log102)2\frac{1 - (1 - 2\log_{10} 2 + (\log_{10} 2)^2 + (\log_{10} 2)^2)}{\log_{10} 2 - (\log_{10} 2)^2}log102−(log102)21−(1−2log102+(log102)2+(log102)2)1−1+2log102−2(log102)2log102−(log102)2\frac{1 - 1 + 2\log_{10} 2 - 2(\log_{10} 2)^2}{\log_{10} 2 - (\log_{10} 2)^2}log102−(log102)21−1+2log102−2(log102)22log102−2(log102)2log102−(log102)2\frac{2\log_{10} 2 - 2(\log_{10} 2)^2}{\log_{10} 2 - (\log_{10} 2)^2}log102−(log102)22log102−2(log102)22(log102−(log102)2)log102−(log102)2\frac{2(\log_{10} 2 - (\log_{10} 2)^2)}{\log_{10} 2 - (\log_{10} 2)^2}log102−(log102)22(log102−(log102)2)=2= 2=23. 最終的な答え2