関連ワード:  integration of x 3 sin 4x dx    integrate x 3 * sin 4 x dx from pi 4 to pi 4    integral of cos 3 x sin 4 x dx    integration of x 3 sin x 4 dx    integration of pi 4 to pi 4 x 3 sin 4x dx    integration of cos 3 x cos 5x sin 2 x sin 4x dx    what is the integral of sin^4x    what is the integration of sin x dx    what is the integral of sin(x)