Solve: cos 3x . sin 5x

1.	Solve: cos 3x . sin 5x
Answer» Let y = cos3x . sin5x (Trans using formula) sy = 2[sin8x – sin(-2x)] = 2 [sin8x] + 2sin2x \(\frac{dy}{dx}\) = 16cos8x + 4cos2x OR Let y = cos 3x . sin 5x \(\frac{dy}{dx}\) = cos3x(5cos5x) + sin5x(-3sin3x) = 5cos3x sin5x – 3sin5x.sin3x.

Answer»

Let y = cos3x . sin5x (Trans using formula)

sy = 2[sin8x – sin(-2x)] = 2 [sin8x] + 2sin2x

\(\frac{dy}{dx}\) = 16cos8x + 4cos2x

OR Let y = cos 3x . sin 5x

\(\frac{dy}{dx}\) = cos3x(5cos5x) + sin5x(-3sin3x) = 5cos3x sin5x – 3sin5x.sin3x.

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