The derivative of y= sin x sin 3x is [tex]$=3 \cos x-3 \cos 3 x$[/tex]
To find the derivative of y= sin x sin 3x:
[tex]$y=3 \sin (x)-\sin (3 x)$[/tex]
[tex]$y^{\prime}=3 \cos x-[\cos (3 x) \cdot 3]$[/tex]
[tex]$y^{\prime}=3(\cos x-\cos 3 x)$[/tex]
[tex]\frac{dx}{dy} =3 cosx - 3 cos x[/tex]
Differentiate [tex]sin 3x[/tex] using the chain rule
Given [tex]y=f^{'} (g(x))*g^{'}[/tex]←chain rule
y=[tex]y=3 sin x-sin 3x[/tex]
[tex]\frac{dx}{dy} =3 cos x - cos 3x*\frac{d}{dx} (3x)[/tex]
[tex]=3cosx-3cos3x[/tex]
To learn more about derivatives, refer to
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