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
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
D.
Let fx = sin4x + cos4x = sin2x + cos2x2 - 2sin2xcos2x = 1 - 14 . 2sin2x2 = 1 - 141 - cos4x = 34 + cos4x4∴ Period of f(x) = π2
cosxcosx - 2y = λ ⇒ tanx - ytany is equal to
1 + λ1 - λ
1 - λ1 + λ
λ1 + λ
cosAcos2Acos4A ... cos2n - 1A equals
sin2nA2nsinA
2nsin2nAsinA
2nsin2nAsin2nA
sinA2nsin2nA
If 3cos(x) ≠ sin x, then the general solution of sin2(x) - cos(2x) = 2 - sin(2x) is
nπ + - 1nπ2, n ∈ Z
nπ2, n ∈ Z
4n ± 1π2, n ∈ Z
2n - 1π, n ∈ Z
In a ∆ABC a + b + cb + c - ac + a - b a + b - c4b2c2 = ?
cos2A
cos2B
sin2A
sin2B