t=x^x,lnt=xlnx,(lnt)'=lnx+1,t'/t=lnx+1,t'=t(lnx+1)=x^x(lnx+1)
y'=x^x(lnx+1)+(ln5)5^x+5x^4-e^-x
dy=[x^x(lnx+1)+(ln5)5^x+5x^4-e^-x]dx