Flag Integral Calculus> integrate (1/1-2acosx+a²).dx limit 0 to p...
question mark

integrate (1/1-2acosx+a²).dx limit 0 to p

Bilal , 11 Years ago
Grade
anser 1 Answers
Rinkoo Gupta
integral 1/(1-2acosx+a^2).dx lim 0 to pie
put cosx=(1-tan^(x/2))/(1+tan^(x/2))
integral sec^2(x/2)dx/(1+a^2)(1+tan^2(x/2))-2a(1-tan^2(x/2)) lim 0 to pie
put tan(x/2)=t
diff. w.r. to x , we get
1/2 sec^(x/2) dx=dt
=2 integral dt/(1-a^2)+(1+a^2)t^2 lim 0 to infinity
=2/(1-a) arctan((1+a)t/(1-a)) lim 0 to infinity
=2/(1-a) [arctan(infinity)-arctan(0)]
=2/(1-a).pie/2
=pie/(1-a)

Thanks & Regards
Rinkoo Gupta
AskIItians Faculty
Last Activity: 11 Years ago
star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments