Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

If 2 sec2 θ - 9 sec θ + 7 = 0, then what is the value of cos2 θ + sec2 θ ?

Options:

2

3

5

1

Correct Answer:

2

Explanation:

2 sec2 θ - 9 sec θ + 7 = 0

2 sec2 θ - 7 sec θ - 2 sec θ + 7 = 0

sec θ ( 2 sec θ - 7 ) - 1 ( 2 sec θ - 7 ) = 0

Either ( 2 sec θ - 7 ) = 0 or  ( sec θ - 1 ) = 0 

( 2 sec θ - 7 ) = 0 is not possible.

&  ( sec θ - 1 ) = 0 

sec θ = 1

So, θ = 0º

Now,

cos2 θ + sec2 θ

= cos2  0º + sec2

= 1 + 1

= 2