Derivatives question help The question is :Find the derivative of $f(x)=e^c + c^x$. Assume that c is a constant.
Wouldn't $f'(x)=   ce^{c-1} + xc^{x-1}$.    It keeps saying this answer is incorrect, What am i doing wrong?

Consider $$f(x)=e^{c}+c^{x}$$ where $c$ is a constant. We know that since $c$ is a constant, $e^c$ is also a constant making ${d\over dx}(e^c)=0$. Also, ${d\over dx}(c^x)=c^x\ln c$. The reason for this is because ${d\over dx}(c^x)={d\over dx}{(e^{\ln c})^x}={d\over dx}({e^{{(\ln c}){x}})}=e^{({\ln c)} x}\cdot {d\over dx} {(\ln c)}x=(e^{\ln c})^x\cdot (\ln c)=c^x\ln c$. Thus $$f'(x)={c^x\ln c}.$$ 
