Derivative of Cos^3(x)*Sin(x) using Chain Rule

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Help!
I last did this kind of work years ago in university. Can som1 please help me with the derivative.
 
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I think the question is ((cosx)^3)*sin(x).Am I right?The formula for d(uv)/dx=u(dv/dx)+v(du/dx).And of course I think you need only formula.Do you need answer?
 
omkar13 said:
I think the question is ((cosx)^3)*sin(x).Am I right?The formula for d(uv)/dx=u(dv/dx)+v(du/dx).And of course I think you need only formula.Do you need answer?
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Thats it chain rule or something:


d(uv)/dx=u(dv/dx)+v(du/dx)

u=sin(x)
v=cos^3(x)

(dv/dx) = -3sin((x))cos^2(x)
(du/dx) = cos(x)

d(uv)/dx= -3sin^2(x)cos^2(x) + cos^4(x)

Is this correct?