Differentiate the following from first principle.

xex

We need to find derivative of f(x) = xex


Derivative of a function f(x) is given by –


f’(x) = {where h is a very small positive number}


derivative of f(x) = xex is given as –


f’(x) =


f’(x) =


f’(x) =


Using algebra of limits, we have –


f’(x) =


f’(x) =


Again Using algebra of limits, we have –


f’(x) =


Use the formula:


f’(x) = ex + xex


f’(x) = ex(x + 1)


Hence,


Derivative of f(x) = xex = ex(x + 1)


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