Integrate:
\[\large \int\limits_{}^{}e^{x^{4}}(x+x^3+2x^5)e^{x^{2}}dx\]
is this an indefinite integral ?
yes
then the error function isnt going to work
can you simplfy the integrand?
i don't know
try by parts separately or use this | e^x (f(x)+f`(x)) = e^x(f(x))
what's f(x) here?
this is what you have to find.... :D
that you got to find int e^(g(x)) (g'(x)f(x)+f'(x)) = e^(g(x))f(x)
put g(x) = x^4 + x^2 and g'(x) f(x) + f'(x) = 2x^5+x^3+x, put the value of g'(x) and find f(x)
i'm not getting pls you solve
look for the particular solution of f(x) that is x^2/2 that should give you your answer is e^(g(x)) x^2/2
we have not studied diff. eq. ,so isn't there any other way to solve?
this is just integration by parts. if you manipulate things carefully you should get the solution. best is to guess your solution that your solution will be of the form e^(x^4+x^2) (ax^2+bx+c)
differentiate it and compare values and solve for a,b,c ... you can guess that your solution will be of the form because the polynomial term is or order ^5
if it were less than x^3, i.e. e^(x^4+x^2) (x^2 + x + c) then an educated guess would be that it wouldn't be integrable in elementary terms.
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