【タイプ1】
(和・差を分けたり、係数を前に出したときに、)基本公式そのままになるもの
\[ \int\frac{1}{\ x^4\ } \ dx \]
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\[ =\int x^{-4} dx \]
\[ =-\frac{1}{ \ 3 \ }x^{-3}+C \]
\[ =-\frac{1}{ \ 3x^{3} \ }+C \]
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\[ \int \left( e^{x} – 2^{x} \right)dx \]
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\[ =\int e^{x} \ dx – \int 2^{x} \ dx \]
\[ =e^{x} – \frac{1}{ \ \log 2 \ } 2^{x} +C \]
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\[ \int \left( \frac{3}{ \ \cos ^{2}x \ } – \frac{2}{ \ \sin ^{2}x \ } \right)dx \]
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\[ =\int \frac{3}{ \ \cos ^{2}x \ } dx-\int \frac{2}{ \ \sin ^{2}x \ } dx \]
\[ =3\int \frac{1}{ \ \cos ^{2}x \ } dx-2\int \frac{1}{ \ \sin ^{2}x \ } dx \]
\[ =3\tan x + \frac{2}{ \ \tan x \ } +C \]
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\[ \int \frac{ \ x^{2} -3x+2 \ }{ x^{2} } \ dx \]
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〔分子の次数〕≧〔分母の次数〕となっている場合、分数を分けることで、
それぞれが〔分子の次数〕<〔分母の次数〕になるように変形する
\[ =\int \left(1- \frac{3}{ \ x \ } + \frac{2}{ \ x^{2} \ } \right)dx \]
\[ =\int \left(1- \frac{3}{ \ x \ } +2 x^{-2} \right)dx \]
\[ =x-3\log|x| -2 x^{-1} +C \]
\[ \left(=x-3\log|x| – \frac{2}{ \ x \ } +C\right) \]
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\[ \int \frac{ \ \sqrt{x} -1 \ }{ \sqrt[3]{x} } dx \]
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\[ =\int \frac{ \ x^{ \frac{1}{2} } -1 \ }{ x^{ \frac{1}{3} } } dx \]
\[ =\int \left( x^{ \frac{1}{6} } – x^{ -\frac{1}{3} } \right)dx \]
\[ =\frac{ \ 6 \ }{7} x^{ \frac{7}{6} } – \frac{ \ 3 \ }{2} x^{ \frac{2}{3} } +C \]
\[ =\frac{ \ 6 \ }{7} x^{ \frac{6}{6} }\cdot x^{ \frac{1}{6} } – \frac{ \ 3 \ }{2} x^{ \frac{2}{3} } +C \]
\[ =\frac{ \ 6 \ }{7} x \cdot \sqrt[6]{x} – \frac{ \ 3 \ }{2} \sqrt[3]{ x^{2} } +C \]
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