FP2: Quick Integration Question Watch
then dx/du = 1/2
so you intergrate: 0.5[1/(1-u^2)]du
and you end up with the right answer
you take the 4 out of the root i.e. 1 / sqrt(4 (1/4)+ x^2) which becomes 1/(2 sqrt( (1/4)+(x^2) )... then take the 1/2 out since its a constant and then integrate 1 / sqrt ( (1/4) + (x^2) ) and multiply the (1/2) at the end...
doing it this way always works for me