Flag Trigonometry> Number of solutions of tanx +secx=2cosx l...
question mark

Number of solutions of tanx +secx=2cosx lying in 0,2×180 is

Siddharthasahul , 8 Years ago
Grade 11
anser 1 Answers
Arun
tan x + sec x = 2cos x 
So , (1+sin x) / cos x = 2cos x 
==> 1 + sin x = 2 cos^2 x 
==> 1 + sin x = 2(1-sin^2 x) 
==> 2sin^2 x + sin x -1 = 0 
==> sin x = -1 or sin x = 1/2 

So there are a total of 3 solutions I think. 

Note: sin x = 1/2 has 2 solutions , 30 and 150 (in degrees) and sin x = -1 has one solution.
Last Activity: 8 Years ago
star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments