If tanθ + tanθ + π3 + tanθ + 2π3 = 3, then which of the following is equal to 1 ?
tan2θ
tan3θ
If α + β + γ = 2θ, then cosθ + cosθ - α + cosθ - β + cosθ - γ = ?
4sinα2 . cosβ2cosγ2
4sinα2 . sinβ2sinγ2
4cosα2 . cosβ2 . cosγ2
4sinα . cosβ . cosγ
x ∈ R : cos2x + 2cos2x = 2 = ?
2nπ + π3 : n ∈ Z
nπ ± π6 : n ∈ Z
nπ + π3 : n ∈ Z
2nπ - π3 : n ∈ Z
1 + tanhx21 - tanhx2 = ?
e - x
ex
2ex2
2e - x2
In ∆ABC, if 1b + c + 1c + a = 3a + b + c, then C is equal to
90°
60°
45°
30°
Observe the following statementsI In ∆ABC, bcos2C2 + ccos2B2 = sII In ∆ABC, cotA2 = b + c2 ⇒ B = 90°Which of the following is correct ?
Both I and II are true
I is true, II is false
I is false, II is true
Both I and II are false
In a triangle, if r1 = 2r2 = 3r3, then ab + bc + ca = ?
7560
15560
17660
19160
D.
Given that, r1 = 2r2 = 3r3∴ ∆s - a = 2∆s - b = 3∆s - c = ∆kThen, s - a = k, s - b = 2k, s - c = 3k⇒ 3s - a + b + c = 6k ⇒ s = 6k∴ a5 = b4 = c3 = kNow, ab + bc + ca = 54 + 43 + 35 = 75 + 80 + 3660 = 19160
From the top of a hill h metres high the angles of depressions of the top and the bottom of a pillar are α and β respectively.The height (in metres) of the pillar is
htanβ - tanαtanβ
htanα - tanβtanα
htanβ + tanαtanβ
htanβ + tanαtanα
The period of sin4x + cos4x is
π42
π22
π4
π2
cosxcosx - 2y = λ ⇒ tanx - ytany is equal to
1 + λ1 - λ
1 - λ1 + λ
λ1 + λ