Differentiate the following functions with respect to x:

(x2 + 1) cos x

Let, y = (x2 + 1) cos x


We have to find dy/dx


As we can observe that y is a product of two functions say u and v where,


u = x2 + 1 and v = cos x


y = uv


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


By product rule, we have –


…equation 1


As, u = x2 + 1



…equation 2 { }


As, v = cos x


…equation 3 { }


from equation 1, we can find dy/dx



{using equation 2 & 3}


Hence,



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