Differentiate each of the following functions by the product by the product rule and the other method and verify that answer from both the methods is the same.

(3x2 + 2)2

Let, y = (3x2 + 2)2 = (3x2 + 2)(3x2 + 2)


y = 9x4 + 6x2 + 6x2 + 4


y = 9x4 + 12x2 + 4


Differentiating y w.r.t x –



Using algebra of derivatives, we have –



Use formula of derivative of above function to get the result.


{


…equation 1


Derivative using product rule –


We have to find dy/dx


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


u = (3x2 + 2) and v = (3x2 + 2)


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 2


As, u = (3x2 + 2)




…..equation 3 { }


As, v = (3x2 + 2)




…equation 4 { }


from equation 2, we can find dy/dx



using equation 3 & 4, we get –




Hence,


….equation 5


Clearly from equation 1 and 5 we observed that both equations gave identical results.


Hence, Results are verified


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