Trigonometry Questions (1127)

If \(\dfrac{1}{2}\sin^{-1}\!\left(\dfrac{3\sin 2\alpha}{5 + 4\cos 2\alpha}\right) = \tan^{-1} x\), then the possible value of \(x\) is:
The period of the function \(f(x) = \sin^4 x + \cos^4 x\) is:
In \(\triangle ABC\), circumradius is 3 and inradius is 1.5 units. If the value of \(a\cot^2 A + b^2\cot^3 B + c^3\cot^4 C\) is \(m\sqrt{n}\) where m and n are prime numbers, then find the value of \(\left(\dfrac{m-1}{n}\right)\).
If \(\dfrac{p-1}{2p+3} = \sin^2\theta + 2\cos\theta + 1\) \(\forall\, \theta \in R\), then \(p\) must lie in the interval:
9. Consider a triangle ABC such that \(\cot A + \cot B + \cot C = \cot \theta\). The possible value of \(\theta\) is:
\(\sin^{-1}\sqrt{\dfrac{x}{x+y}} = \tan^{-1}(\underline{\quad})\).
The value of \(\cos^2 10° - \cos 10° \cos 50° + \cos^2 50°\) is
The least value of \(\csc^2 x + 25\sec^2 x\) is
If \(\tan A\) and \(\tan B\) are the roots of the quadratic equation, \(3x^2-10x-25=0\), then the value of \(3\sin^2(A+B)-10\sin(A+B)\cos(A+B)-25\cos^2(A+B)\) is
Given a triangular plot ABC with sides AB = 7 m, BC = 5 m and CA = 6 m. A vertical lamp-post at the mid-point D of AC subtends an angle 30° at B. Find the height of the lamp-post.
Given \(\cos^{-1}\left(\dfrac{2}{3x}\right) + \cos^{-1}\left(\dfrac{3}{4x}\right) = \dfrac{\pi}{2}\)Find the value of \(x\).
The value of \(\sin\sqrt{x^2 - \frac{\pi^2}{36}}\) lies in the interval
Maximum possible perimeter of the triangle is :
Given \(\tan\theta = \dfrac{-4}{3}\), find \(\sin\theta\).
If \(y = \sqrt{t} + \sqrt{(\pi/2) - t}\) where \(t = \sin^{-1} x\), \(x \in [0, \pi/2]\), then the maximum value of \(y\) is:
If \(p = \cos 55°\), \(q = \cos 65°\) and \(r = \cos 175°\), then the value of \(\dfrac{1}{p} + \dfrac{1}{q} + \dfrac{r}{pq}\) is equal to:
173. If \(\cos x + \cos^2 x = 1\). Let \(E = \sin^{12} x + 3\sin^{10} x + 3\sin^8 x + \sin^6 x + 2\), then the value of \(\log_{\tan\frac{\pi}{3}} E\) is:
Find the value of \(x\), if \(\tan^{-1}\dfrac{yz}{rx} + \tan^{-1}\dfrac{zx}{ry} + \tan^{-1}\dfrac{xy}{rz} = x^\circ\) and \(r^2 = x^2 + y^2 + z^2\).
If a, b, c be the sides of a triangle ABC and the roots of the equation \(a(b-c)x^2 + b(c-a)x + c(a-b) = 0\) are equal, then \(\sin^2\left(\dfrac{A}{2}\right), \sin^2\left(\dfrac{B}{2}\right), \sin^2\left(\dfrac{C}{2}\right)\) are in
Given that the roots of the equation \(2x^2 - 10x - 25 = 0\) are \(\tan A\) and \(\tan B\), find the value of \(3\sin^2(A+B) - 10\sin(A+B)\cos(A+B) - 25\cos^2(A+B)\).
If \(\displaystyle\sum_{r=1}^{100} \sin^{-1}\!\left(\frac{1}{\sqrt{r^2+1}\sqrt{r^2+2r+2}}\right)\) is equal to \(\tan^{-1}\!\left(\dfrac{p}{q}\right)\) where \(p\) and \(q\) are co-prime, then the value of \((p+q)\) is equal to:
160. If \(\cos^{-1}\!\left(\dfrac{2}{3x}\right) + \cos^{-1}\!\left(\dfrac{3}{4x}\right) = \dfrac{\pi}{2}\) \(\left(x > \dfrac{3}{4}\right)\), then \(x\) is equal to:
If \(\cos A = \cos B\) and \(\sin A = \sin B\) then
If in a triangle ABC; ∠C = π/8; a = √2; b = √(2 + √2) then the measure of ∠A can be:
If A > 0, B > 0 and A + B = π/6, then the maximum value of tan A + tan B is:
If \(\frac{1}{3} \leq \sin x a.
Let \(\sec x + \tan x = \frac{22}{7}\), where \(0
If \(\cos^{-1}x+\cos^{-1}y+\cos^{-1}z=3\pi\), then \(xy+yz+zx=\)
\(\displaystyle\lim_{n\to\infty}\sum_{r=1}^{n}\tan^{-1}\!\frac{2r+1}{r^4+2r^3+r^2+1}=\)
In a triangle \(ABC\), \(2ca\sin\dfrac{A-B+C}{2}\) is equal to
\(\sin^{-1}(\sin 5)>x^2-4x\) holds for:
If $a$ and $b$ are the roots of the equation $4x^2 - 3x + a = 0$, sin $A + \cos A + \tan A + \cot A + \sec A + \cos A = 7$ and $0 < A < \frac{\pi}{2}$, then the value of $a$ must be
The value of the expression \(\dfrac{\sin^2\dfrac{2\pi}{7} + \sin^2\dfrac{4\pi}{7} + \sin^2\dfrac{\pi}{7}}{\sin^2\dfrac{\pi}{7} + \sin^2\dfrac{2\pi}{7} + \sin^2\dfrac{4\pi}{7}}\) is equal to:
Solve \(\theta = \tan^{-1}(2\tan^2\theta) - \frac{1}{2}\sin^{-1}\left(\frac{3\sin 20}{5 + 4\cos 20}\right)\).
Solve for \(x\): \(\tan^{-1} x + \tan^{-1}(1-x) = \cot^{-1}\frac{7}{9}\), where \(x \in (0,1)\).
Two poles of heights 20 m and 80 m are standing on a horizontal ground. The height (in metres) of the point of intersection of the lines joining the top of each pole to the foot of the other pole is:
If \(|2x + \sin^2 a| + |2x + 3 + 2\sin a| = 0\) and \(4\lambda^2 = 1\), find \(4\lambda^2\).
A man is walking towards a vertical pillar in a straight path, at a uniform speed. At a certain point A on the path, he observes that the angle of elevation of the top of the pillar is 30°. After walking for 10 min from A in the same direction, at a point B, he observes that the angle of elevation of the top of the pillar is 60°. Then, the time taken (in minutes) by him, from B to reach the pillar, is
If \(\sin^{-1}\!\sqrt{x/2}+\sin^{-1}\!\sqrt{1-x/4}+\tan^{-1}y=\frac{2\pi}{3}\), then which are true?
Let a and b be the lengths of the legs of a right triangle with the following properties: (a) All 3 sides of the triangle are integers. (b) The perimeter of the triangle is numerically equal to area of the triangle, it is given that a < b. The number of ordered pairs (a, b) will be :
The value of \(S = \dfrac{\sin^2\dfrac{2\pi}{7}}{\sin^2\dfrac{\pi}{7}} + \dfrac{\sin^2\dfrac{4\pi}{7}}{\sin^2\dfrac{2\pi}{7}} + \dfrac{\sin^2\dfrac{\pi}{7}}{\sin^2\dfrac{4\pi}{7}}\) is:
If ABCD is a cyclic quadrilateral then \(\cos A + \cos B + \cos C + \cos D\) is equal to
A tower stands at the centre of a circular park. A and B are two points on the boundary of the park such that AB (= a) subtends an angle of 60° at the foot of the tower, and the angle of elevation of the top of the tower from A or B is 30°. The height of the tower is
A $150\left(\sqrt{3}+1\right)$ ft.
Which are correct?(A) \(\cot^{-1}x=\tan^{-1}(1/x)\ \forall x\in\mathbb{R}\setminus\{0\}\)(B) \(f(x)=\text{sgn}(e^x)\) is into(C) \(f:\mathbb{R}^+\to\mathbb{R},\,f(x)=\sin x+x\) is odd(D) \(f(x)=e^x/e^{[x]}\) is periodic
\(\sin[\cot^{-1}\{\tan(\cos^{-1} x)\}]\) is equal to
The number of possible solutions of x such that \(\sin^2 x + \cos^2 x = 1\) is:
Let \(a \in \left(\dfrac{-\pi}{2}, \dfrac{\pi}{2}\right)\) such that \(\tan^{-1}\!\left(\dfrac{\tan\alpha}{3 + 2\tan^2\alpha}\right) + \tan^{-1}\!\left(\dfrac{2\tan\alpha}{3}\right) = \dfrac{\pi}{12}\), then \(\alpha\) equals:
811. In \(\triangle ABC\), if \(\sin A \sin B \sin C + \cos A \cos B = 1\) then the value of \(\cos^2 A + \sin^2 B + 2\sin^2 \dfrac{C}{2}\) is:
If \(2\le a