Verify the identity 14 sec2 x 12 sec x 12 sec x choose the
Verify the identity.
1-4 sec^2 x / 1-2 sec x = 1+2 sec x
choose the sequence of steps below that verifies the identity
a) 1-4 sec^2 x / 1-2 sec x= (2-sec x)(2-sec x)/ 1-2 sec x = 1+2 sec x
b) 1-4 sec^2 x / 1-2 sec x= (1-2 sec x)(1-2 sec x)/ 1-2 sec x= 1+2 sec x
c) 1-4 sec^2 x / 1-2 sec x= (2+ sec x) (2- sec x)/ 1-2 sec x= 1+2 sec x
d) 1-4 sec^2 x / 1-2 sec x= (1+2 sec x)(1-2 sec x)/1-2 sec x= 1+2 sec x
Solution
(1-4 sec^2 x) / (1-2 sec x) = 1+2 sec x
LHS : (1-4 sec^2 x) / (1-2 sec x)
= (1 -2secx)(1+2secx)/( 1- 2secx)
= 1+ 2secx
Option d
