B

9000035704

Level: 
B
Find the polar form of the complex number \( A \) graphed in the complex plane as shown in the picture.
\(z = 2\sqrt{2}\left (\cos \frac{3\pi } {4} + \mathrm{i}\sin \frac{3\pi } {4}\right )\)
\(z = 2\sqrt{2}\left (\cos \frac{\pi }{4} -\mathrm{i}\sin \frac{\pi }{4}\right )\)
\(z = 2\sqrt{2}\left (-\cos \frac{\pi }{4} + \mathrm{i}\sin \frac{\pi }{4}\right )\)
\(z = 2\sqrt{2}\left (\cos \frac{5\pi } {4} + \mathrm{i}\sin \frac{5\pi } {4}\right )\)

9000035601

Level: 
B
Find the values of the parameter \(p\in \mathbb{R}\) which guarantee that the following quadratic equation has solutions with nonzero imaginary part. \[ px^{2} - 3x + 4p = 0 \]
\(p\in \left (-\infty ;-\frac{3} {4}\right )\cup \left (\frac{3} {4};\infty \right )\)
\(p\in\left (-\frac{3} {4}; \frac{3} {4}\right )\)
\(p\in\left (\frac{3} {4};\infty \right )\)
\(p\in\left \{-\frac{3} {4}; \frac{3} {4}\right \}\)
\(p\in\mathbb{R}\setminus \left \{-\frac{3} {4}; \frac{3} {4}\right \}\)

9000035805

Level: 
B
Given the complex numbers \[ \text{$a = 2\left (\cos \frac{2\pi } {3} + \mathrm{i}\sin \frac{2\pi } {3}\right )$, $b = \sqrt{2}\left (\cos \frac{3\pi } {4} + \mathrm{i}\sin \frac{3\pi } {4}\right )$,} \] find the product \(ab\).
\(2\sqrt{2}\left (\cos \frac{17\pi } {12} + \mathrm{i}\sin \frac{17\pi } {12}\right )\)
\(2\sqrt{2}\left (\cos \frac{\pi }{2} + \mathrm{i}\sin \frac{\pi }{2}\right )\)
\(2\sqrt{2}\left (\cos \frac{5\pi } {7} + \mathrm{i}\sin \frac{5\pi } {7}\right )\)
\(2\sqrt{2}\left (\cos \frac{5\pi } {12} + \mathrm{i}\sin \frac{5\pi } {12}\right )\)

9000035806

Level: 
B
Given the complex numbers \[ \text{ $a = 2\left (\cos \frac{5\pi } {3} + \mathrm{i}\sin \frac{5\pi } {3}\right )$, $b = 3\left (\cos \frac{11\pi } {6} + \mathrm{i}\sin \frac{11\pi } {6} \right )$,} \] find the quotient \(\frac{a} {b}\).
\(\frac{2} {3}\left (\cos \frac{11\pi } {6} + \mathrm{i}\sin \frac{11\pi } {6} \right )\)
\(\frac{2} {3}\left (\cos \frac{\pi } {6} + \mathrm{i}\sin \frac{\pi } {6}\right )\)
\(\frac{2} {3}\left (\cos \frac{5\pi } {6} + \mathrm{i}\sin \frac{5\pi } {6}\right )\)
\(\frac{2} {3}\left (\cos \frac{7\pi } {6} + \mathrm{i}\sin \frac{7\pi } {6}\right )\)

9000034906

Level: 
B
The solution set of one of the following quadratic inequalities is \(\left (-\infty ;-\frac{3} {5}\right )\cup \left (\frac{1} {6};\infty \right )\). Determine this inequality.
\(\left (5x + 3\right )\left (1 - 6x\right ) < 0\)
\(\left (5x - 3\right )\left (6x + 1\right ) < 0\)
\(\left (5x + 3\right )\left (1 - 6x\right ) > 0\)
\(\left (5x - 3\right )\left (6x + 1\right ) > 0\)

9000034907

Level: 
B
Find all \(x\in \mathbb{R}\) for which the following expression takes nonnegative values. \[ -2\left (x - 3\right )\left (2 - x\right ) \]
\(\left (-\infty ;2\right ] \cup \left [ 3;\infty \right )\)
\(\left [ 2;3\right ] \)
\(\left (2;3\right )\)
\(\left (-\infty ;2\right )\cup \left (3;\infty \right )\)

9000034908

Level: 
B
Find all \(x\in \mathbb{R}\) for which the following expression is nonpositive. \[ \left (x + 1\right )\left (4 + x\right ) \]
\(\left [ -4;-1\right ] \)
\(\left (-\infty ;-4\right ] \cup \left [ -1;\infty \right )\)
\(\left (-4;-1\right )\)
\(\left (-\infty ;-4\right )\cup \left (-1;\infty \right )\)

9000035003

Level: 
B
The tree of the height \(12\, \mathrm{m}\) is observed from the place horizontal with the base of the tree. The angle of elevation is \(10^{\circ }\). Find the distance of the observer from the base and round to the nearest meters.
\(68\, \mathrm{m}\)
\(2\, \mathrm{m}\)
\(12\, \mathrm{m}\)
\(48\, \mathrm{m}\)