Find the sum to n terms: tan y sec 2y + tan 2y sec 4y + tan 4y sec 8y + …

Find the second derivative of (i) y = sec x - tan x

Find the derivative of : y = tan ^-1 (sec x + tan x )

If (tan A + sec A) (tan B + sec B) (tan C + sec C) = (tan A -sec A) (tan B -secB) (sec C-tan C),show that each side is equal to +-1

If (sec A + tan A)(sec B + tan B)(sec C + tan C) = (sec A- tan A)(sec B- tan B)(sec C tan C) Prove that each side is equal to +-1.

Find the derivate of y = e^(sec x) .

Find the equation of the tangents to the circle x ^2 + y ^2 - 2x - 4y - 4 = 0 which are perpendicular to the line 3x - 4y - 1 = 0

Find the derivative of : y = sec (tan^-1 x)

Find the derivate of y = x^(sec^-1 x) .

Find dy/dx : y = log(sec x+ tan x)

Find the derivate of y =e^(tan^2x) .