`int_0^pi dx/(1-2acosx+a^2), alt1` is equal to (A) `(pialog2)/4` (B) `(4pi)/(2-a^2)` (C) `pi/(1-a^2)` (D) none of these

int_(0)^(pi)(1)/(a^(2)-2acosx+1)dx,agt1 is equal to

int _(-pi//2)^(pi//2) (dx)/(1+cosx) is equal to

int_(0)^(oo)(xdx)/((1+x)(1+x^(2))) is equal to (A)(pi)/(4) (B) (pi)/(2)(C)pi(D) none of thesel

int_-pi^(3pi) cot^-1(cotx)dx= (A) pi^2 (B) 2pi^2 (C) 3pi^2 (D) none of these

int_0^pi cos2xlogsinxdx= (A) pi (B) -pi/2 (C) pi/2 (D) none of these

The value of int_(-2 pi)^(5 pi)cot^(-1)(tan x)dx is equal to (7 pi)/(2)(b)(7 pi^(2))/(2)(c)(3 pi)/(2) (d) None of these

int_0^oo logx/(1+x^2)dx= (A) log2 (B) pi/2 (C) 0 (D) none of these

cos^(-1)(cos(2cot^(-1)(sqrt(2)-1))) is equal to sqrt(2)-1( b) (pi)/(4)(c)(3 pi)/(4) (d) none of these

int_0^21/(1+tanx)dx is equal to (pi^)/4 (b) (pi^)/3 (c) (pi^)/2 (d) pi

int_(0)^(oo)((pi)/(1+pi^(2)x^(2))-(1)/(1+x^(2)))log xdx is equal to (a)-(pi)/(2)ln pi(b)0(c)(pi)/(2)ln2(d) none of these