Question

Integrate cos(2-t^2)

Answer 1

I don't think you can integrate that...

Answer 2

I didn't either but apparently its integratable....

Answer 3

@Euler271 what do you think?

Answer 4

it isn't integratable using standard calculus methods since it is not an elementary function.

who told you it was?

here is what the answer is: http://www.wolframalpha.com/input/?i=integrate+cos%282-+t%5E2%29

Answer 5

well honestly I assumed it was doable because it was on one of my tests in the past and I had no idea where to start

Answer 6

it must have been slightly different, like t*cos(2 - t^2), or not calculus

Answer 7

no it was definitely cos(2-t^2)

Answer 8

ok well thanks anyway

Answer 9

if its possible, could you help me on this question too? its-
If dx/dt=(2t+1)/2x
and x(1)=3 find x(0). I know how to separate them but im not sure what the next step is

Answer 10

\[x dx = \frac{ (2t+1) }{ 2 } dt\]integrate both sides\[\frac{ x^2 }{ 2 } = \frac{ t^2 + t }{ 2 } + C_1\]isolate x\[x(t) = \pm \sqrt{t^2 + t + C_2}\]let x(1) = 3
\[3 = \pm \sqrt{1 + 1 + C_2}\]solve for C. since x(1) = +3, we an deduce that + is the proper sign (not minus).\[9 = 2 + C_2\]it's 7. plug it back in:\[x(t) = \sqrt{t^2 + t + 7}\]
to find x(0), plug t = 0\[x(0) = + \sqrt{7}\]

Answer 11

ohh ok, I see it now. I should have added c when I square rooted

Answer 12

yup ^_^

Answer 13

thank you sooo much!

Answer 14

glad i could help C: