해법
∫sin4(x)cos6(x)dx
해법
61cos5(x)sin(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))−1011(81cos7(x)sin(x)+87(61cos5(x)sin(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))+101cos9(x)sin(x)+C
솔루션 단계
∫sin4(x)cos6(x)dx
삼각성을 사용하여 다시 쓰기
=∫(1−cos2(x))2cos6(x)dx
(1−cos2(x))2cos6(x)확대한다:cos6(x)−2cos8(x)+cos10(x)
=∫cos6(x)−2cos8(x)+cos10(x)dx
합계 규칙 적용: ∫f(x)±g(x)dx=∫f(x)dx±∫g(x)dx=∫cos6(x)dx−∫2cos8(x)dx+∫cos10(x)dx
∫cos6(x)dx=6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))
∫2cos8(x)dx=2(8sin(x)cos7(x)+87(6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))
∫cos10(x)dx=10sin(x)cos9(x)+109(8sin(x)cos7(x)+87(6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))
=6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))−2(8sin(x)cos7(x)+87(6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))+10sin(x)cos9(x)+109(8sin(x)cos7(x)+87(6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))
6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))−2(8sin(x)cos7(x)+87(6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))+10sin(x)cos9(x)+109(8sin(x)cos7(x)+87(6sin(x)cos5(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))간소화하다 :61cos5(x)sin(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))−1011(81cos7(x)sin(x)+87(61cos5(x)sin(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))+101cos9(x)sin(x)
=61cos5(x)sin(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))−1011(81cos7(x)sin(x)+87(61cos5(x)sin(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))+101cos9(x)sin(x)
솔루션에 상수 추가=61cos5(x)sin(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))−1011(81cos7(x)sin(x)+87(61cos5(x)sin(x)+65(41cos3(x)sin(x)+83(x+21sin(2x)))))+101cos9(x)sin(x)+C