Differentiate:

ex cos x


To find: Differentiation of ex cos x


Formula used: (i) (uv)′ = u′v + uv′ (Leibnitz or product rule)


(ii)


(iii)


Let us take u = ex and v = cosx




Putting the above obtained values in the formula:-


(uv)′ = u′v + uv′


(ex cosx)’ = ex× cosx + ex× -sinx


= excosx - exsinx


= ex (cosx - sinx)


Ans) ex (cosx - sinx)


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