How do you integrate by substitution int (t+2t^2)/sqrtt dtt+2t2tdt?

1 Answer
Dec 26, 2017

int(t+2t^2)/sqrt(t)dt=2sqrt(t^3)/3+4sqrt(t^5)/5+Ct+2t2tdt=2t33+4t55+C

Explanation:

We see a sqrt(t)t our first thought is to substitude u=sqrt(t)u=t.

So let's do that :

u=sqrt(t)=>du=1/(2sqrt(t))dt=>dt=2sqrt(t)du=>dt=2uduu=tdu=12tdtdt=2tdudt=2udu

So our integral becomes :

int(t+2t^2)/sqrt(t)dt=int(u^2+2u^4)/u*2udu=2int(u^2+2u^4)du=t+2t2tdt=u2+2u4u2udu=2(u2+2u4)du=

2(u^3/3+2u^5/5)+C=2u^3/3+4u^5/5+C2(u33+2u55)+C=2u33+4u55+C

Now let's substitude u=sqrt(t)u=t back in :

int(t+2t^2)/sqrt(t)dt=2sqrt(t^3)/3+4sqrt(t^5)/5+Ct+2t2tdt=2t33+4t55+C