Question

Find the integral off...

(intergrand) 5x cos x^2 dx

Answer 1

\[\int\limits_{}^{}5xcos^2(x)dx\]

Answer 2

this is the question ?

Answer 3

yes

Answer 4

I worked it out but am not sure if it is correct, I dont want to go wolfram it....

Answer 5

use u-subst it will work
let u=x^2

Answer 6

wait this is the question \[\int\limits_{0}^{0} x^5 \cos x^2 dx\]

Answer 7

oh, which one that question ?

Answer 8

disregard the 0 on the integrals

Answer 9

the one I just posted above is the correct one

Answer 10

I just fully mucked that up. I apologize everyone. This is the question \[\int\limits_{?}^{?}5x \cos x^2 dx\]

Answer 11

Im a dumbass so sorry about this

Answer 12

but, for integral f(x) with interval from a to a, it can be zero... right, @Coolsector ?

Answer 13

disregard the zeros on the integrals, I didnt know how to remove them

Answer 14

i think he wants indefinite integral

Answer 15

use u sub as RadEn suggested

Answer 16

ohhhhhh, lol

Answer 17

u=x^2 then du=2xdx

Answer 18

then your integral becomes 2.5 cos(u)du

Answer 19

the cos will turn into sin?

Answer 20

yes integrating this will give you 2.5sin(u)
which is 2.5sin(x^2)

Answer 21

you can verify your answer by differentiating 2.5sin(x^2) and getting 5xcos(x^2)
so it is correct :)

Answer 22

I got without substitution
\[f(x) =\frac{ 5 }{ 2 } \sin x^2\]

Answer 23

it is good ..

Answer 24

ok great, thank you guys

Answer 25

dont forget constant of integration +C ;)

Answer 26

yes thats right, my teachers nemonic for that is cough, so you need vit c to boost your imune lol

Answer 27

Yes but it still deserves a 0 on a test because you forgot to add a constant c.

Answer 28

so, without intervals ?

Answer 29

LOL

Answer 30

Without intervals it's called an indefinite integral.

Answer 31

ok thank you guys.