解
∫tan(x)(sec2(x))dx
解
−22(−81(ln2cot(x)+22cot(x)+2−2arctan(2cot(x)+1))+81(ln2cot(x)−22cot(x)+2+2arctan(2cot(x)−1)))+xtan23(x)−arctan(tan(x))tan23(x)−221ln2tan(x)+22tan(x)+2−21arctan(2tan(x)+1)+221ln2tan(x)−22tan(x)+2−21arctan(2tan(x)−1)+2tan(x)+C
解答ステップ
∫tan(x)sec2(x)dx
三角関数の公式を使用して書き換える
=∫tan(x)1+tan2(x)dx
拡張 tan(x)1+tan2(x):tan(x)1+tan23(x)
=∫tan(x)1+tan23(x)dx
総和規則を適用する: ∫f(x)±g(x)dx=∫f(x)dx±∫g(x)dx=∫tan(x)1dx+∫tan23(x)dx
∫tan(x)1dx=−22(−81(ln2cot(x)+22cot(x)+2−2arctan(2cot(x)+1))+81(ln2cot(x)−22cot(x)+2+2arctan(2cot(x)−1)))
∫tan23(x)dx=xtan23(x)−arctan(tan(x))tan23(x)−221ln2tan(x)+22tan(x)+2−21arctan(2tan(x)+1)+221ln2tan(x)−22tan(x)+2−21arctan(2tan(x)−1)+2tan(x)
=−22(−81(ln2cot(x)+22cot(x)+2−2arctan(2cot(x)+1))+81(ln2cot(x)−22cot(x)+2+2arctan(2cot(x)−1)))+xtan23(x)−arctan(tan(x))tan23(x)−221ln2tan(x)+22tan(x)+2−21arctan(2tan(x)+1)+221ln2tan(x)−22tan(x)+2−21arctan(2tan(x)−1)+2tan(x)
定数を解答に追加する=−22(−81(ln2cot(x)+22cot(x)+2−2arctan(2cot(x)+1))+81(ln2cot(x)−22cot(x)+2+2arctan(2cot(x)−1)))+xtan23(x)−arctan(tan(x))tan23(x)−221ln2tan(x)+22tan(x)+2−21arctan(2tan(x)+1)+221ln2tan(x)−22tan(x)+2−21arctan(2tan(x)−1)+2tan(x)+C