The value of sec4 (1 - sin4) - 2tan2 is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 1
Here it is given that,
= sec4(1 - sin4) - 2tan2
= 1/cos4( 1 - (sin2)2) - 2 × sin2/cos2
= 1/cos2(1 - sin2) × (1 + sin2)(1 - sin2) - 2 × sin2/cos2
= (1 + sin2)/ cos2 - 2 × sin2/cos2
= ( 1 + sin2 - 2sin2)/ cos2
= cos2/ cos2
= 1.