If sin (∝ - β) = 1/2 and cos (∝ + β) = 1/2, where ∝ and β are positive acute angles, then:
∝ = 45o
β= 15o
∝= 15o, β = 45o
∝ = 60o, β = 15o
The expression tan2∝+ cot2 ∝ is
≥ 2
≤ 2
≥ -2
= 2
If tan A = - 1/2 and tan B = - 1/3, then A+B =
∏/4
3 ∏/4
5∏/4
None of these
If cos θ = 1/2 (x + 1/x), then 1/2 (x2 + 1/x2) is equal to
sin 2 θ
cos 2 θ
tan 2 θ
sec2 θ
Sin 2 θ
Cos 2θ
Cosec 2 θ
Sec 2 θ
The value of cos 15o is
If sin θ + cos θ = m and sec θ + cosec θ = n, then n (m+1) (m-1) is equal to
m
n
2m
2n
The value of 1+ cos 56o + cos 58o - cos 66o is equal to
2 cos 28o cos 29o cos 33o
4 cos 28o cos 29o cos 33o
4 cos 28o cos 29o sin 33o
2 cos 28o cos 29o sin 33o
If sin θ + cosec θ = 2, then sin2 θ + cosec2 θ is equal to
1
2
4
6
The value of Cos2θ + Sec2θ is always
Less than 1
Equal to 1
Greater than 1, but less than 2
Greater than or equal to 2