" 11: "cos^(4)2x

Prove that, "cos" pi/11 "cos" (2pi)/11 "cos" (3pi)/11 "cos" (4pi)/11 "cos" (5pi)/11 = 1/32

Find the extreme values of 11 cos^(2) x+ 15 sin x cos x- 9 sin^(2) x .

int_-1^1 x^11 cos^4 x dx is equal to :

If cos x=t a n x , then which of the following is true? (a) 1/(sinx)+cos^4x=1 (b) 1/(sinx)+cos^4x=2 (c) cos^(54)x+cos^2x=1 (d) cos^4x+cos^2x=2

int_(0)^(11)cos x-cos^(2)x+cos^(3)x-cos^(4)x+...oo dx

cos ((pi) / (11)) cos (2 (pi) / (11)) cos (3 (pi) / (11)) cos (4 (pi) / (11)) cos (5 (pi) / (11))

cos ((pi) / (11)) cos ((2 pi) / (11)) cos ((3 pi) / (11)) ... cos ((11 pi) / (11)) =

5. if the expression cos^2(pi/11)+cos^2((2pi)/11)+cos^2((3pi)/11)+cos^2((4pi)/11)+cos^2((5pi)/11) has the value equal to p/q in it lowest from ; then find (p+q)

If the expression cos^2(pi/11)+cos^2((2pi)/11)+cos^2((3pi)/11)+cos^2((4pi)/11)+cos^2((5pi)/11) has the value equal to p/q in it lowest from ; then find (p+q)