LFM Pure

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gaokao 2024 Q6 4 marks View
Given $f ( x ) = \sin \omega x , f \left( x _ { 1 } \right) = - 1 , f \left( x _ { 2 } \right) = 1 , \left| x _ { 1 } - x _ { 2 } \right| _ { \text {min} } = \frac { \pi } { 2 }$, then $\omega =$ \_\_\_\_
gaokao 2024 Q7 5 marks View
When $x \in [ 0,2 \pi ]$ , the number of intersection points of the curves $y = \sin x$ and $y = 2 \sin \left( 3 x - \frac { \pi } { 6 } \right)$ is
A. $3$
B. $4$
C. $6$
D. $8$
gaokao 2024 Q9 6 marks View
For functions $f ( x ) = \sin 2 x$ and $g ( x ) = \sin \left( 2 x - \frac { \pi } { 4 } \right)$, the correct statements are
A. $f ( x )$ and $g ( x )$ have the same zeros
B. $f ( x )$ and $g ( x )$ have the same maximum value
C. $f ( x )$ and $g ( x )$ have the same minimum positive period
D. The graphs of $f ( x )$ and $g ( x )$ have the same axes of symmetry
gaokao 2024 Q12 5 marks View
Given $\alpha \in \left[ \frac { \pi } { 6 } , \frac { \pi } { 3 } \right]$, and the terminal sides of $\alpha$ and $\beta$ are symmetric about the origin, then the maximum value of $\cos \beta$ is \_\_\_\_.
gaokao 2025 Q4 5 marks View
If the point $(a, 0)$ $(a > 0)$ is a center of symmetry of the graph of the function $y = 2\tan\left(x - \frac{\pi}{3}\right)$, then the minimum value of $a$ is
A. $\frac{\pi}{4}$
B. $\frac{\pi}{2}$
C. $\frac{\pi}{3}$
D. $\frac{4\pi}{3}$
gaokao 2025 Q15 13 marks View
Given the function $f(x) = \cos(2x + \varphi)$ $(0 \leq \varphi < \pi)$, $f(0) = \frac{1}{2}$.
(1) Find $\varphi$;
(2) Let $g(x) = f(x) + f\left(x - \frac{\pi}{6}\right)$. Find the range and monotonic intervals of $g(x)$.
grandes-ecoles 2010 QI.A.1 Trigonometric Identity Proof or Derivation View
For every integer $n \in \mathbb{N}$, we set $F_n(x) = \cos(n \arccos x)$.
a) Show that the functions $F_n$ are defined on the same domain $D$ which should be specified.
b) Calculate $F_1(x), F_2(x)$ and $F_3(x)$ for all $x \in D$.
c) Calculate $F_n(1), F_n(0)$ and $F_n(-1)$ for all $n \in \mathbb{N}$.
d) Specify the parity properties of $F_n$ as a function of $n$.
iran-konkur 2013 Q103 View
103- The figure shows part of the graph of $y = a\sin\pi\!\left(\dfrac{1}{2} + bx\right)$. What is $a \cdot b$?
[Figure: Graph of a sinusoidal function with amplitude $2$, showing values at $x = 3.5$ and minimum $-2$, with dashed line at $y=2$]
  • [(1)] $2$
  • [(2)] $2.5$
  • [(3)] $3$
  • [(4)] $3.5$
iran-konkur 2013 Q110 View
110- What is the value of $\tan^{-1}\sqrt{x^2 + x} + \sin^{-1}\sqrt{x^2 + x + 1}$?
(1) $\dfrac{\pi}{4}$ (2) $\dfrac{\pi}{2}$ (3) $\dfrac{3\pi}{4}$ (4) $\pi$
iran-konkur 2022 Q113 View
113. The figure below shows a portion of the graph of $f(x) = a\cos(bx + c)$. If $b > 0$, $0 < c < \pi$, and $\dfrac{ac}{b} = 0$, what is the value?
[Figure: Graph of a cosine function with amplitude $\frac{1}{3}$, showing one full cycle. The graph reaches a minimum of $-\frac{1}{3}$ and passes through key points at $x = \frac{3}{4}$ and $x = \frac{5}{4}$]
(1) $\dfrac{1}{16}$
(2) $1$
(3) $\dfrac{1}{4\pi}$
(4) $\pi$
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isi-entrance 2012 Q14 View
Which of the following is true about $\tan(\sin x)$?
(A) $\tan(\sin x) = 1$ has solutions
(B) $\tan(\sin x) \geq 1$ for some $x$
(C) $\tan(\sin x) < 1$ for all $x$
(D) $\tan(\sin x)$ never attains the value $1$
isi-entrance 2012 Q25 View
For $\theta \in (0, \pi/2)$, which of the following is true?
(A) $\cos(\sin\theta) < \cos\theta$
(B) $\cos(\sin\theta) < \sin(\cos\theta)$
(C) $\cos(\sin\theta) > \cos\theta$
(D) $\cos(\sin\theta) > \sin(\cos\theta)$
isi-entrance 2013 Q35 4 marks View
The value of $$\sin ^ { - 1 } \cot \left[ \sin ^ { - 1 } \left\{ \frac { 1 } { 2 } \left( 1 - \sqrt { \frac { 5 } { 6 } } \right) \right\} + \cos ^ { - 1 } \sqrt { \frac { 2 } { 3 } } + \sec ^ { - 1 } \sqrt { \frac { 8 } { 3 } } \right]$$ is
(A) 0
(B) $\pi / 6$
(C) $\pi / 4$
(D) $\pi / 2$
isi-entrance 2016 Q35 4 marks View
The value of $$\sin ^ { - 1 } \cot \left[ \sin ^ { - 1 } \left\{ \frac { 1 } { 2 } \left( 1 - \sqrt { \frac { 5 } { 6 } } \right) \right\} + \cos ^ { - 1 } \sqrt { \frac { 2 } { 3 } } + \sec ^ { - 1 } \sqrt { \frac { 8 } { 3 } } \right]$$ is
(A) 0
(B) $\pi/6$
(C) $\pi/4$
(D) $\pi/2$
In the range $0 \leq x \leq 2 \pi$, the equation $\cos ( \sin ( x ) ) = \frac { 1 } { 2 }$ has
(A) 0 solutions.
(B) 2 solutions.
(C) 4 solutions.
(D) infinitely many solutions.
If the maximum and minimum values of $\sin ^ { 6 } x + \cos ^ { 6 } x$, as $x$ takes all real values, are $a$ and $b$, respectively, then $a - b$ equals
(A) $\frac { 1 } { 2 }$.
(B) $\frac { 2 } { 3 }$.
(C) $\frac { 3 } { 4 }$.
(D) 1 .
isi-entrance 2026 Q4 View
The value of $\sin ^ { - 1 } \cot \left[ \sin ^ { - 1 } \left\{ \frac { 1 } { 2 } \left( 1 - \sqrt { \frac { 5 } { 6 } } \right) \right\} + \cos ^ { - 1 } \sqrt { \frac { 2 } { 3 } } + \sec ^ { - 1 } \sqrt { \frac { 8 } { 3 } } \right]$ is
(a) 0 .
(B) $\pi / 6$.
(C) $\pi / 4$.
(D) $\pi / 2$.
21. The incentre of the triangle with vertices $( 1 , \sqrt { 3 } ) , ( 0,0 )$ and $( 2,0 )$ is :
(A) $( 1 , \sqrt { } 3 / 2 )$
(B) $( 2 / 3,1 / \sqrt { } 3 )$
(C) $( 2 / 3 , \sqrt { } 3 / 2 )$
(D) $( 1,1 / \sqrt { } 3 )$
jee-advanced 2015 Q50 View
If $\alpha = 3 \sin ^ { - 1 } \left( \frac { 6 } { 11 } \right)$ and $\beta = 3 \cos ^ { - 1 } \left( \frac { 4 } { 9 } \right)$, where the inverse trigonometric functions take only the principal values, then the correct option(s) is(are)
(A) $\quad \cos \beta > 0$
(B) $\quad \sin \beta < 0$
(C) $\quad \cos ( \alpha + \beta ) > 0$
(D) $\quad \cos \alpha < 0$
jee-main 2007 Q102 Inverse trigonometric equation View
If $\sin ^ { - 1 } \left( \frac { x } { 5 } \right) + \operatorname { cosec } ^ { - 1 } \left( \frac { 5 } { 4 } \right) = \frac { \pi } { 2 }$ then a value of $x$ is
(1) 1
(2) 3
(3) 4
(4) 5
The chord $PQ$ of the parabola $y ^ { 2 } = x$, where one end $P$ of the chord is at point $( 4 , - 2 )$, is perpendicular to the axis of the parabola. Then the slope of the normal at $Q$ is
(1) $-4$
(2) $- \frac { 1 } { 4 }$
(3) $4$
(4) $\frac { 1 } { 4 }$
jee-main 2013 Q69 View
Let $x \in ( 0,1 )$. The set of all $x$ such that $\sin ^ { -1 } x > \cos ^ { -1 } x$, is the interval:
(1) $\left( \frac { 1 } { 2 } , \frac { 1 } { \sqrt { 2 } } \right)$
(2) $\left( \frac { 1 } { \sqrt { 2 } } , 1 \right)$
(3) $( 0,1 )$
(4) $\left( 0 , \frac { \sqrt { 3 } } { 2 } \right)$
jee-main 2014 Q76 Inverse trigonometric equation View
The principal value of $\tan ^ { - 1 } \left( \cot \frac { 43 \pi } { 4 } \right)$ is
(1) $\frac { \pi } { 4 }$
(2) $- \frac { \pi } { 4 }$
(3) $\frac { 3 \pi } { 4 }$
(4) $- \frac { 3 \pi } { 4 }$
The function $f ( x ) = | \sin 4 x | + | \cos 2 x |$, is a periodic function with a fundamental period
(1) $\pi$
(2) $2 \pi$
(3) $\frac { \pi } { 4 }$
(4) $\frac { \pi } { 2 }$
Let $S = \left\{ \theta \in [ 0,2 \pi ] : 8 ^ { 2 \sin ^ { 2 } \theta } + 8 ^ { 2 \cos ^ { 2 } \theta } = 16 \right\}$. Then $n ( S ) + \sum _ { \theta \in \mathrm { S } } \left( \sec \left( \frac { \pi } { 4 } + 2 \theta \right) \operatorname { cosec } \left( \frac { \pi } { 4 } + 2 \theta \right) \right)$ is equal to:
(1) 0
(2) $- 2$
(3) $- 4$
(4) 12