problem: 1/(4-x^2)
(ill be using o to represent theta)
x=sino
dx=2coso do
sin=x/2
integrate 1/2coso * 2coso do = integrate do
Looking at the triangle I draw I can tell that i screwed up somewhere but the form a-x is sin
the answer I end up with is arcsin(x/2) but I know it should be arctan(x/2) i just cant make it work.
You made a mistake working out 4-x^2
If we sub x=2sino 4-x^2 becomes 4cos^2o and you get an integral you can't do
Do you know about partial fractions. If you partial fraction the question you get an integral you can do (if you have learnt about differentiating logs)