The minimum value of 27tan2θ + 3cot2θ is
15
18
24
30
cos36° - cos72° = ?
1
12
14
If tanx + tanx + π3 + tanx + 2π3 = 3,then tan3x = ?
3
2
0
If 3sinx + 4cosx = 5, then 6tanx2 - 9tan2x2 = ?
If α, β, γ are length of the altitudes of a ∆ABC with area ∆, then ∆2R21α2 + 1β2 + 1γ2 = ?
sin2A + sin2B + sin2C
cos2A + cos2B + cos2C
tan2A + tan2B + tan2C
cot2A + cot2B + cot2C
In an acute angled triangle, cot(B)cot(C) + cot(A)cot(C) + cot(A)cot(B) = ?
- 1
x = log1y + 1 + 1y2 ⇒ y = ?
tanhx
cothx
sechx
cschx
The period of f(x) = cosx3 + sinx2 is
2π
4π
8π
12π
If sinθ + cosθ = p and sin3θ + cos3θ = q, then p(p2 - 3) is equal to
q
2q
- q
- 2q
D.
Given, sinθ + cosθ = p ...i and sin3θ + cos3θ = q ...ii⇒ sinθ + cosθsin2θ - sinθcosθ + cos2θ = q⇒ p1 - sinθcosθ = q From eq i and sin2θ + cos2θ = 1⇒ 1 - sinθcosθ = qp
sinθcosθ = 1 - qp ...iiiOn squaring both sides of eq i, we getsin2θ + cos2θ + 2sinθcosθ = p2⇒ 1 + 21 - qp = p2 from eq iii⇒ p + 2p - q = p3⇒ 3p - 2q = p3⇒ p3 - 3p = - 2q⇒ pp2 - 3 = - 2q
If tanπcosθ = cotπsinθ, then a value of cosθ - π4 among the following is
122