" (8) "[" EL ",1-cos x sqrt(cos2x)],[x^(2)," x' "]

lim_(x rarr0)(1-cos x sqrt(cos2x))/(x^(2))

lim_(x rarr0)(1-cos x sqrt(cos2x))/((e^(x)^^2-1))

"cos" 2x =(sqrt(2) + 1) ("cos"x- (1)/(sqrt(2))),"cos" x ne (1)/(2) rArr x in

"cos" 2x =(sqrt(2) + 1) ("cos"x- (1)/(sqrt(2))),"cos" x ne (1)/(2) rArr x in

If tanx=b/a then sqrt((a+b)/(a-b))+sqrt((a-b)/(a+b))= ........................... A) (2 sin x)/(sqrt(sin2x)) B) (2 cos x)/(sqrt(cos2x)) C) (2 cos x)/(sqrt(sin2x)) D) (2 sin x)/(sqrt(cos2x))

If "sin" x + "sin"^(2) x = 1 show that: cos^(4)x + cos^(2)x = 1 (ii) If "sin" x + cos x =sqrt(2) cos x show that: sqrt2 sin x = cos x - sin x

cos^(-1)x sqrt(3)+cos^(-1)x=(pi)/(2)

Lt_(x to 0)(sqrt(1-cos2x))/(sqrt(2)x)=

The value of cos^-1 x + cos^-1 {x/2 + sqrt3/2 cdot sqrt(1 - x^2)}, x gt 1/2 is

cos^-1((x)/sqrt(1+x^2))