This ques has been taken from
Book- ML Aggarwal
Board- ICSE
Publication- Avichal
Chapter- Trigonometric Identities
Chapter number-18
We hage have to prove
(i) tan A + cot A = sec A cosec A
(ii) (1 – cos A) (1 + sec A) = tan A sin A
Ques no. 13, chapter 18th trigonometry identities
Solution:
(i) L.H.S. = tan A + cot A
= sin A/cos A + cos A/sin A
= (sin2 A + cos2 A)/ (sin A cos A)
= 1/ (sin A cos A)
= sec A cosec A
= R.H.S
(ii) L.H.S. = (1 – cos A) (1 + sec A)