Question

cat este integrala din xe la -x dx

Answer 1

$\int\limits x*e^-^x\, dx$=

$(e^-^x)'=e^-^x(-x)' = -e^-^x$


[tex] \int\limits (-e^-^x)' *x \, dx = -e^-^x*x- \int\limits -e^-^x * (x)'\, dx= [/tex]

[tex]=-e^-^x*x- \int\limits -e^-^x \, dx =-e^-^x*x+ \int\limits e^-^x{x} \, dx= [/tex]

$-e^-^x*x-e^-^x+C$