Question

Solve the integral:
\[\int\limits_{-\infty}^{+\infty}(1+x^{2})/dx\]

Answer 1

dx is in the denominator?

Answer 2

yeap there is a /

Answer 3

So, you're pretty much asking us to find\[\int(1+x^2)\frac{1}{dx},\]which in words translates to "the integral of 1+x^2 with respect to the inverse of x?

This has got to be the first time I encounter such statement!

Answer 4

Change "the inverse of x" with "the reciprocal of x." ^^

Answer 5

I did not get what you mean with "Change "the inverse of x" with "the reciprocal of x.""

Answer 6

across, you're in a playful mood today.

In short, this expression as you've written it is meaningless. What you almost certainly mean is
\[ \int_{-\infty}^{\infty} \frac{dx}{1+x^2} \]

Answer 7

That's why i did not get what she said

Answer 8

yes..try as i might..this expression korcan doesnt make sense

Answer 9

What James said. Math has got to make sense. n_O

Answer 10

even when it doesn't

Answer 11

it does not, if it was making any sense, then I would not date with girls

Answer 12

whats that supposed to mean now?

Answer 13

that's one too many negations for me.

Confirm what I've written is correct and then there are quite a few people here who can help you.

Answer 14

We are jus moving on a bad way, from math to philasophy :)

Answer 15

if james is right then the answer is pi

Answer 16

Don't give me the fish, teach me how to catch some fish, so I can feed myself, so explain the solution and how can I solve this type of integration?

Answer 17

if what he wrote is correct , can we use change of variable?

Answer 18

You can solve the one James wrote by looking at a table of common integrals.

Answer 19

then the answer is pi

Answer 20

\[\int(1+1/u^2)du\]

?

Answer 21

bcz the indefinit integral if dx/(1+x^2) is arctanx

Answer 22

yeap tan^-1(x)