(i) (cosec θ – cot θ)² = (1-cos θ)/(1 + cos θ) (ii) (cos A)/(1 + sin A) + (1 + sin A)/(cos A) = 2 sec A (iii) (tan θ)/(1 – cot θ) + (cot θ)/(1 – tan θ) ...

(i) (sin 18°)/(cos 72°) (ii) (tan 26°)/(cot 64°) (iii) cot 48° – sin 42° (iv) cosec 31° – sec 59° NCERT Class 10 Chapter 8 Introduction to trigonometry Page No. 189 Exercise 8.3 Question No. 1

(i) The value of tan A is always less than 1. (ii) sec A = 12/5 for some value of angle A. (iii) cos A is the abbreviation used for the cosecant of angle A. (iv) cot A is the ...