0000:00:00:00:00Start28Number 28ExplanationThe first derivative of y=cos3xy = \cos^3 xy=cos3x is ....3cosx⋅sinx3\cos x \cdot \sin x3cosx⋅sinx−3cosx⋅sinx-3\cos x \cdot \sin x−3cosx⋅sinx2cosx⋅sin2x2\cos x \cdot \sin 2x2cosx⋅sin2x−6cosx⋅sin2x-6\cos x \cdot \sin 2x−6cosx⋅sin2x−32cosx⋅sin2x\frac{-3}{2}\cos x \cdot \sin 2x2−3cosx⋅sin2x
28Number 28ExplanationThe first derivative of y=cos3xy = \cos^3 xy=cos3x is ....3cosx⋅sinx3\cos x \cdot \sin x3cosx⋅sinx−3cosx⋅sinx-3\cos x \cdot \sin x−3cosx⋅sinx2cosx⋅sin2x2\cos x \cdot \sin 2x2cosx⋅sin2x−6cosx⋅sin2x-6\cos x \cdot \sin 2x−6cosx⋅sin2x−32cosx⋅sin2x\frac{-3}{2}\cos x \cdot \sin 2x2−3cosx⋅sin2x
