Mathematics
Assertion (A): If ∠A = 30°, the value of tan2 2A - sec2 2A is 1.
Reason (R): tan2 2A - sec2 2A = tan2 60° - sec2 60°
=
- A is true, R is false.
- A is false, R is true.
- Both A and R are true.
- Both A and R are false.
Trigonometric Identities
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Answer
A is false, R is true.
Explanation
Given, tan2 2A - sec2 2A
= tan2 (2 x 30°) - sec2 (2 x 30°)
= tan2 60° - sec2 60°
=
= 3 - 4
= -1
∴ Assertion (A) is false.
From the above calculation,
tan2 2A - sec2 2A = -1
∴ Reason (R) is true.
Hence, Assertion (A) is false, Reason (R) is true.
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