Trigonometry Functions - Test Questions-iii

Question 11

Question:  
tan (x + y) and tan (x - y).

Answer:   

Question 12

Question:  

Answer:    Since x lies in II quadrant, cos x is negative.

Question 13

Question:  

Answer:   

Question 14

Question:  

Answer:   

Question 15

Question:  

Answer:   

Question 16

Question:   Prove that tan x = cotx - 2 cot 2x.

Answer:   
[Add and subtract cos²x in the N^r]

Question 17

Question:  

Answer:   

Question 18

Question:  

Answer:   

Question 19

Question:  

Answer:   

Question 20

Question:  

Answer:   










By componendo and dividendo, we get