Find dy/dx of y=e^xcosx

Use product rule i.e. (uv)'=u'v+uv'Set u=e^x and differentiate to find u'=e^x Set v=cosx and differentiate to find v'=-sinxTherefore (uv)' where uv=e^xcosx =e^xcosx + e^x(-sinx)=e^xcosx - e^xsinx=e^x(cosx -sinx)

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