Question

I need some serious help with double integrals.

Answer 1

\[\int\limits_{\pi}^{o} \int\limits_{1}^{0} xsin(xy) dydx\]

please be thorough

Answer 2

im sorry reverse those integrals to 0 to pi and 0 to 1

Answer 3

first we will integrate xsin(xy) and treat x as a constant and y is the variable of integration

Answer 4

so integral of xsin(xy)dy will be
-xcos(xy)/x
-cos(xy)

Answer 5

understand so far ?

Answer 6

ya

Answer 7

so if we plug in limits we get
-cos(x) - [-cos(0)] = -cos(x) + 1

Answer 8

now we have to integrate -cox(x) + 1dx
this is a one variable integral
so
-sin(x) + x now again plug in limits
-sin(pi) + pi - [-sin(0) + 0] = pi

Answer 9

thanks alot

Answer 10

@calculusfunctions no .. you are wrong.

Answer 11

no :O

Answer 12

integral of 5sin(5y) is 5 * (-cos(5y) /5 )

Answer 13

no y involved downstairs ..

Answer 14

wolfram agree with me anyway.

Answer 15

@Coolsector yes actually you're correct about the y.

Answer 16

ty

Answer 17

LOL Careless mistakes!