Differentiate the following functions with respect to x:

x3 ex cos x


Let, y = x3 ex cos x


We have to find dy/dx


As we can observe that y is a product of three functions say u, v & w where,


u = x3


v = cos x


w = ex


y = uvw


As we know that to find the derivative of product of three function we apply product rule of differentiation.


By product rule, we have –


…equation 1


As, u = x3


…equation 2 { }


As, v = cos x


…equation 3 { }


As, w = ex


…equation 4 { }


from equation 1, we can find dy/dx



using equation 2, 3 & 4, we have –



Hence,



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