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Help with 2 integral problems

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khanvict

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1) integral [e^(arctan x) / (1+x^2)]dx

i know proof: arctan = 1/(1+x^2)


2) integral [4dt / (t(5+(ln t)^2)]

i know proof: d/dx arcsec = 1 / (x*sqrt(x^2-1))


i am stuck on both of these so any help is appreciated. thanks in advance!

Added after 4 hours 12 minutes:

here is what i did with the 2nd:

integral 4 dt / (t [ 5 + (ln 2)^2 ])

rewritten:
integral [ 4 / t * ( 1 / (5 + (ln t)^2) ) ]
and again:
integral [ (4t^-1) * ( 1 / (5 + (ln t)^2) ) ]

trying to get the 2nd half in proof form of: arctan = (du / 1 + u^2)
& noting that proof: x^p = ln x + c if p = -1

i ended up with:
(1/5)t * [(4 ln t) * arctan(ln t)] + c

i have no idea if that's correct but i only have 2 hours left so i have to go with it.
anyone reading this know how to do the 1st by any chance?
 

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