Need some help soving this double integral:

integral sign (0 to 1) integral sign (tan^-1(y) to pi/4) secx dxdy.

Please bear with my notation.

Help will be appreciated.

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- Nov 16th 2012, 07:01 PMmrmaaza123Double integration
Need some help soving this double integral:

integral sign (0 to 1) integral sign (tan^-1(y) to pi/4) secx dxdy.

Please bear with my notation.

Help will be appreciated. - Nov 16th 2012, 09:03 PMchiroRe: Double integration
Hey mrmaaza123.

In this forum you should be able to evaluate the dx limits first then then the dy limits after.

Try doing that by integrating sec(x)dx with the appropriate limits and show us what you got. - Nov 16th 2012, 09:52 PMmrmaaza123Re: Double integration
Well i actually did get that far, and got

integral sign (0 to 1) ln(sqrt2 +1)+ln((sec(tan)^-1(y)) +y) dy

then i used the identity (tan(x))^2+1 = (sec(x))^2 to get ,

integral sign (0 to 1) ln(sqrt2+1) - ln(sqrt(y^2+1) +y) dy

this is where i got stuck. Do i proceed using by parts ? - Nov 16th 2012, 09:57 PMchiroRe: Double integration
I'd give parts a go and see what you get by setting dv = 1 and u = ln(sqrt(y^2 + 1) + y). You should get rid of the logarithm and the rest will be simpler.