143. Which of the following identities are correct?
i) 1+sin theta/cos theta + cos theta/1+ sin theta = 2 sec theta
ii) (1+ cot A - cosec A)(1+ tanA + secA)= 2
iii) root 1+sin theta/ 1-sin theta = |sec theta + tan theta|
iv) cos theta/1+sin theta + cos theta/ 1- sin theta = 2 sec theta
Consider the equation,
--------(1)
Now, numerator resembles the identity (a + b) (a - b) = (a 2 - b 2)
Where, a = (sin A + cos A), b = 1, so equation (1) is
Now, we know (Sin2A + Cos2A) = 1, so the last equation is
