Flag Trigonometry> If sec θ = x + 1/4x , x ≠ 0 , then how ca...
question mark

If sec θ = x + 1/4x, x ≠ 0, then how can (sec θ – tan θ) be expressed as?

Rishabh Sankla , 6 Years ago
Grade 11
anser 1 Answers
Arun
Given:
 
secϴ = x + 1/4x…….(1)
 
tan²ϴ = sec²ϴ -1
tan²ϴ =  (x + 1/4x)² -1  
 
[From equation 1]
 
tan²ϴ = x² + 1/16x² +½ -1
[ (a+b)² = a² + 2ab +b²]
 
tan²ϴ = x² + 1/16x² - ½
tan²ϴ = (x - 1/4x)²
 
[a² +b²-2ab = (a-b)²]
tanϴ = ±(x - 1/4x)
 
[Taking square roots both sides]
tanϴ = (x - 1/4x) or - (x - 1/4x)
When tanϴ =  (x - 1/4x), then  
secϴ +tanϴ = x +1/4x + x -1/4x = 2x
 
[From equation 1]
 
secϴ +tanϴ = 2x
 
When tanϴ = - (x - 1/4x), then  
secϴ +tanϴ = (x +1/4x) -( x -1/4x )  
 [From equation 1]
 
=  x +1/4x - x + 1/4x   
= 1/4x + 1/4x = 2/4x = 1/2x
Hence secϴ - tanϴ = 2x
 
ApprovedApproved
Last Activity: 6 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