2000005407
Level:
B
Determine the smallest period of the function \(f(x)=2\cos 3x\).
\( \frac{2}{3}\pi\)
\( 2\pi\)
\( \frac{1}{3}\pi\)
\( \frac{1}{4}\pi\)
B
2000005406
Level:
B
Which of the following statements is not true?
Functions \(f(x)=\cos\left(x+\frac{\pi}{6}\right)\) and \(g(x)=\sin\left(x-\frac{\pi}{6}\right)\) are equal.
Functions \(f(x)=2-\cos 3x\) is even and its range of values is \([ 1;3]\).
Functions \(f(x)=\cos\left(x-\frac{\pi}{3}\right)\) and \(g(x)=\sin\left(x+\frac{\pi}{6}\right)\) are equal.
Functions \(f(x)=\cos x\) and \(g(x)=\sin\left(x+\frac{\pi}{2}\right)\) are equal.
2000005405
Level:
B
Which of the following statements is true?
All values of the function \(f(x)=2-\cos x\) are positive.
Function \(f(x)=\mathrm{tg}\,x\) is increasing over the whole domain.
The smallest positive period of the function \(f(x)=\sin 4x\) is \(\frac{\pi}{4}\).
Function \(f(x)=1+\sin x\) is an odd function.
2000005404
Level:
B
Which of the following statements is true?
\( \sin 700^{\circ} = \sin 200^{\circ} \)
\( \cos 550^{\circ} = \cos 10^{\circ} \)
\( \mathrm{tg}\, 20^{\circ} = \mathrm{tg}\, (-20^{\circ}) \)
\( \cos 520^{\circ} = \cos 20^{\circ} \)
2000005402
Level:
B
What is the measure of the angle \(x\), \(x \in [ 0;2\pi)\), for which \(\cos x = \frac{\sqrt{2}}{2}\) and \(\mathrm{tg}\,x < 0 \)?
\( \frac{7}{4}\pi\)
\( \frac{1}{4}\pi\)
\( \frac{3}{4}\pi\)
\( \frac{5}{4}\pi\)
2000005403
Level:
B
What is the measure of the angle \(x\), \(x \in [ 0;2\pi)\), for which \(\mathrm{tg}\,x = -1\) and \(\sin x >0\)?
\( \frac{3}{4}\pi\)
\( \frac{5}{4}\pi\)
\( \frac{1}{4}\pi\)
\( \frac{7}{4}\pi\)
2000005401
Level:
B
What is the measure of the angle \(x\), \(x \in [ 0;2\pi)\), for which \(\sin x = -\frac{1}{2}\) and \(\cos x < 0\)?
\( \frac{7}{6}\pi\)
\( \frac{5}{6}\pi\)
\( \frac{11}{6}\pi\)
\( \frac{1}{6}\pi\)
2000005305
Level:
B
Find all real values of \(x\) such that the fraction \( \frac{7}{x^2+1} \) is negative.
\( \emptyset \)
\( x \in \mathbb{R} \)
\( x \in (-1;+\infty) \)
\( x \in \mathbb{R}\setminus \{ \pm 1\}\)
2000005304
Level:
B
Find all real values of \( x\) such that the fraction \( \frac{5}{x^2}\) is positive.
\( x \in \mathbb{R}\setminus \{0\}\)
\( x \in \mathbb{R}\)
\( x \in (0;+\infty)\)
\( x \in [ 0;+\infty)\)
2000004702
Level:
B
A part of a rectangle drawn on the wall is painted in yellow (see the picture). Imagine a bee landing on a random spot of the rectangle. What is the probability of the bee landing on the yellow part?
\( \frac{3}{8} \)
\( \frac{1}{3} \)
\( \frac{1}{8} \)
\( \frac{5}{8} \)