`u=log[tan(pi/4+theta/2)]` whose per. If u = log (tan (+9), then prove that cosh u = sec e.

If x = log [ tan (pi/4 + theta/2 ) ] then cosh x =

If u = log (tan x + tan y + tanz) , prove that sum sin 2x (delu)/(delx) = 2

If x=log_(e)[tan((pi)/(4)+(theta)/(2))] then cos hx=

If x=log_(e)[tan((pi)/(4)+(theta)/(2))] then cos hx=

If theta in ((-pi)/(4), (pi)/(4)) and x=log_(e )[cot((pi)/(4)+theta)] then prove that (i) cosh x= sec 2theta" " (ii) sinh x=-tan 2theta

If u=log_(e )"Tan"((3pi)/(4)+(theta)/(2)) then coshu=

Prove that tan ((pi )/(4) + (theta )/(2) ) + tan ((pi )/(4) - (theta)/(2)) = 2 sec theta.

If u=log((x^(2) + y^(2))/(xy)) , then