Substituting the values of sin2A=2sinAcosA and cos2A=2cos2A−1, we get
2sinAcosA1+2cos2A−1
=2sinAcosA2cos2A=tanA
We know, tan2A=2tanA1−tan2A
So, tanA=2tanA21−tan2A2
How many of below given statements are correct?
1. sin2A = 2sinA.cosA
2.cos2A = sin2A−cos2A
3.tan A = 2tanA21−tan2A2
4. sin2A2 = 1 - cosA
5. tan2A = 1−cos2A1+cos2A
6. sin2A = 2tanA1−tan2A
sin2A1+cos2A =
If A = 30∘, verify that:
(i) sin 2A=2 tan A1+tan2 A (ii) cos 2A=1−tan2 A1+tan2 A (iii) tan 2A=2 tan A1−tan2 A