Inverse Trigonometry Questions (1043)

Given, $\frac{b+c}{11} = \frac{c+a}{12} = \frac{a+b}{13}$ for a triangle ABC with $\frac{\cos A}{\alpha} = \frac{\cos B}{\beta} = \frac{\cos C}{\gamma}$, then the ordered triad $(\alpha, \beta, \gamma)$ has a value
The equation \((\cos p - 1)x^2 + \cos p \cdot x + \sin p = 0\) where \(x\) is a variable, has real roots. Then the interval of possible values of \(p\) is
A train travelling on one of two intersecting railway lines, subtends at a certain station on the other line, an angle \(\alpha\) when the front of the carriage reaches the junction and an angle \(\beta\) when the end of the carriage reaches it. The two lines are inclined to each other at an angle \(\theta\). Then \(2\cot\theta\) is equal to
Consider a triangle ABC and let a, b and c denote the lengths of the sides opposite to vertices A, B and C, respectively. If a = 1, b = 3 and C = 60°, then \(\sin^2 B\) is equal to
The number of solutions of \(\sin 3x = \cos 2x\), in the interval \(\left(\dfrac{\pi}{2}, \pi\right)\) is
An aeroplane flying at a height of \(\sqrt{3}\) km above the ground passes vertically above another plane at an instant when the angles of elevation of the two planes from a point on the ground are \(60°\) and \(30°\) respectively. The distance (in km) between the two planes at that instant is:
If sin A / sin B = 5/2 and cos A / cos B = 3/2, where 0 , then
If 0 x x which satisfy the equation cos x + cos 2x + cos 3x + cos 4x = 0 is:
If $A(n) = (\sin 1) \times (\sin 2) \times \cdots \times \sin(n), \forall n \in \mathbb{N}$, then the number of elements in the set $A = \{f(1), f(2), \ldots, f(6)\}$ that are positive are
If \(\tan(\alpha - \beta) = \dfrac{\sin(2\beta)}{3 - \cos(2\beta)}\), then \(\tan\alpha = f(\beta)\). The value of \(f\!\left(\dfrac{\pi}{3}\right)\) equals:
If x and y are non-zero real numbers satisfying xy(x2 − y2) = x2 + y2, then find the minimum value of x2 + y2.
The expression cos²(A - B) + cos² B - 2cos(A - B)cos A cos B is
Let x + y + z = θ and k = 2. If \(\cos x + \cos y + \cos z = k\cos\theta\) and \(\sin x + \sin y + \sin z = k\sin\theta\), find the value of \(\cos(x+y) + \cos(y+z) + \cos(z+x)\).
If \(A\), \(B\), \(C\) are in AP and \(B = \frac{\pi}{4}\) then \(\tan A \cdot \tan B \cdot \tan C =\) ______
Given that \(\cos(\alpha + \beta) = \dfrac{4}{5}\) and \(\sin(\alpha - \beta) = \dfrac{5}{13}\), where \(\alpha + \beta \in \left[0, \dfrac{\pi}{2}\right]\) and \(\alpha - \beta \in \left[0, \dfrac{\pi}{4}\right]\), then \(\tan 2\alpha\) is equal to:
The sum of solutions in \((0, 2\pi)\) of the equation \(\cos x \cos\!\left(\dfrac{\pi}{3} - x\right)\cos\!\left(\dfrac{\pi}{3} + x\right) = \dfrac{1}{4}\) is:
If \(\cos 2\theta = \sin\alpha\) then the most general relation between \(\theta\) and \(\alpha\) is (where \(n \in \mathbb{Z}\))
A tower \(T_1\) of height 60 m is located exactly opposite to a tower \(T_2\) of height 80 m on a straight road. From the top of \(T_1\), if the angle of depression of the foot of \(T_2\) is twice the angle of elevation of the top of \(T_2\), then the width (in m) of the road between the feet of the towers \(T_1\) and \(T_2\) is
Paragraph (Questions 7-8): Let the incircle of \(\triangle ABC\) touch sides \(BC, CA, AB\) at \(A_1, B_1, C_1\) respectively. The incircle of \(\triangle A_1B_1C_1\) touches its sides \(B_1C_1, C_1A_1, A_1B_1\) at \(A_2, B_2, C_2\) respectively and so on.Find \(\lim_{n \to \infty} \angle A_n\)
If \(\cos^2 x = t\), and the equation \(5\left[\frac{1-t}{t} - t\right] = 2(2t-1) + 9\) is satisfied, then find the value of \(\cos 4x\).
With the usual notation, in triangle ABC, if $\angle A + \angle B = 120°$, $a = \sqrt{3} + 1$ and $b = \sqrt{3} - 1$, then the ratio $\angle A : \angle B$ is
If in the pedal triangle DEF of an acute-angled triangle ABC, the sides are denoted by l, m, n, then l/(a²) + m/(b²) + n/(c²) is equal to
If \(\tan\theta_1, \tan\theta_2, \tan\theta_3\) are the real roots of the equation \(x^3 - (a+1)x^2 + (b-a)x - b = 0\), where \(\theta_1 + \theta_2 + \theta_3 \in (0, \pi)\), then \(\theta_1 + \theta_2 + \theta_3\) is equal to
AB is a vertical pole with B at the ground level and A at the top. A man finds that the angle of elevation of point A from a certain point C on the ground is 60°. He moves away from the pole along the line BC to a point D such that CD = 7 m. From D the angle of elevation of the point A is 45°. Then the height of the pole is
\(3 \csc 20° - \sec 20°\) is equal to
The value of \(\sqrt{3}\csc 20° - \sec 20°\) is equal to
The number of values of \(x\) in \([0, 5\pi]\) satisfying the equation \(3\sin^2 x - 7\sin x + 2 = 0\) is
Solution set of the inequality \((\cot^{-1}x)^2 - 5(\cot^{-1}x) + 6 > 0\) is
In triangle ABC, given a/sin A = 2√2/sin 30° = 4/sin C. Find angles C and A.
Two flagstaffs stand on a horizontal plane. A and B are two points on the line joining their feet and between them. The angles of elevation of the tops of the flagstaffs as seen from A are 30° and 60° and as seen from B are 60° and 45°. If AB is 30 m, the distance between the flagstaffs in metres is
If sin θ + cos θ = a and sin³ θ + cos³ θ = b, then the value of λ³ + μ³ + ν³ is, where λa + μb + νa = 0 and λ, μ, ν are independent of θ.
The value of expression \(\frac{8}{1 + \tan(100°)}\) is equal to
If $\dfrac{\cos^248°-\sin^212°}{\sin^224°-\sin^26°}=\dfrac{\alpha+\beta\sqrt{5}}{2}$, where $\alpha,\beta\in\mathbb{N}$, then $\alpha+\beta$ is equal to _____.
If $a\sin\theta - b\cos\theta = -\sin 4\theta$ and $a\cos\theta + b\sin\theta = \frac{5}{2} - \frac{3}{2}\cos 4\theta$, then $(a+b)^{2/5} + (a-b)^{2/5}$ is _______.
If $\tan\left(142\frac{1}{2}°\right) = 2 + \sqrt{2} - \sqrt{\mu} - \sqrt{\lambda}$, then $\mu + \lambda =$
The general solution of sin 2θ sec θ + √3 tan θ = 0.
Two parallel chords are drawn on the same side of the centre of a circle of radius R. It is found that they subtend an angle of θ and 2θ at the centre of the circle. The perpendicular distance between the chords is
Which of the following is the least?(a) \(\sin 3\)(b) \(\sin 2\)(c) \(\sin 1\)(d) \(\sin 7\)
In a triangle ABC, if \(\tan\frac{A}{2}\tan\frac{C}{2} = \frac{1}{3}\) and \(ac = 4\), then the least value of b is:(notation have their usual meaning)
Statement I: \(\tan 50° - \tan 30° - \tan 20° = \tan 50° \tan 30° \tan 20°\)Statement II: If \(x = y + z\), then \(\tan x - \tan y - \tan z = \tan x \tan y \tan z\)
In a triangle ABC, if \(\tan A = 2 \sin 2C\) and \(3 \cos A = 2 \sin B \sin C\) then possible values of C is/are:
The minimum value of the function f(x) = sin x/√(1 - cos² x) + cos x/√(1 - sin² x) + tan x/√(sec² x - 1) + cot x/√(cosec² x - 1) whenever it is defined is
Angles A, B and C of a △ABC are in AP. If \(\frac{b}{c} = \frac{\sqrt{3}}{2}\), then ∠A is equal to
The complete set of values of x satisfying the inequality sin-1(sin 5) > x2 - 4x is ( 2 - √(1 - 2π), 2 + √(1 - 2π) ), then l =
If \(\sec A \tan B + \tan A \sec B = 91\), then the value of \((\sec A \sec B + \tan A \tan B)^2\) is equal to:
Let ABC be a right triangle with $\angle BAC = \frac{\pi}{2}$, then $\left(\frac{r_2}{2R^2} + \frac{r}{R}\right)$ is equal to: (where symbols used have usual meaning in a triangle)
In triangle ABC, if \(2a^2b^2 + 2b^2c^2 = a^4 + b^4 + c^4\), then angle B is equal to
All positions of point P for which triangle DEF is isosceles lie on
If \(x + \frac{1}{x} = 2\), the principal value of \(\sin^{-1}x\) is
If \(\dfrac{1}{16}(\cos 36^\circ \sin 54^\circ)^2 - \left(\dfrac{1}{4}\sin 36^\circ \sin 36^\circ\right)^2 \equiv \dfrac{\sqrt{a}-b}{c}\), find \((a + b + c)\).