Evaluate
the integral from 0 to 4 of
(x+1)/(16+x^2) dx
the answers are log(sqrt2) + pi/16
Could you please take me through how to get to that answer please, thank you very much!
split (x+1)/(16+x^2) into x/(16+x^2) + 1/(16+x^2)
the integral of x/(16+x^2) = (1/2) ln(16+x^2)
( I recognized the ln derivative pattern)
for the integral of 1/(16+x^2) I went to my "archaic" integral talbles and go
(1/4) tan^-1 (x/4)
so the integral would be
(1/2)ln(16+x^2) + (1/4)tan^-1 (x/4)
so from 0 to 4 would give me
( (1/2)ln(32) + (1/4)tan^-1 (1) - ( (1/2) ln16 + (1/4)tan^-1 (0) )
= ln √32 + (1/4)(π/4) - ln √16 - (1/4)(0)
= ln (4√2) + π/16 - ln 4 - 0
= ln4 + ln √2 + π/16 - ln4
= ln √2 + π/16