Question

sec x=0.9,find 1-sec^2 (x)/1+sec^2 (x)

Answer 1

Correct option is
C
2
Given,

secx+sec
2
x=1

⇒secx=1−sec
2
x=tan
2
x

⇒sec
2
x=tan
4
x

⇒1+tan
2
x=tan
4
x

(1+tan
2
x)
2
=(tan
4
x)
2


1+tan
4
x+2tan
2
x=tan
8
x

∴tan
8
x−tan
4
x−2tan
2
x+1

=1+tan
4
x+2tan
2
x−tan
4
x−2tan
2
x+1

=2