B

9000038604

Level: 
B
Find the polar form of the following complex number. \[ \frac{\sqrt{3}} {\sqrt{2}} + \mathrm{i}\frac{\sqrt{3}} {\sqrt{2}} \]
\(\sqrt{3}\left (\cos \frac{\pi }{4} + \mathrm{i}\sin \frac{\pi }{4}\right )\)
\(\sqrt{3}\left (\cos \frac{3\pi } {4} + \mathrm{i}\sin \frac{3\pi } {4}\right )\)
\(\sqrt{2}\left (\cos \frac{\pi }{3} + \mathrm{i}\sin \frac{\pi }{3}\right )\)
\(\sqrt{2}\left (\cos \frac{2\pi } {3} + \mathrm{i}\sin \frac{2\pi } {3}\right )\)

9000038605

Level: 
B
Find the polar form of the following complex number. \[ -\frac{\sqrt{5}} {2} + \mathrm{i}\frac{\sqrt{15}} {2} \]
\(\sqrt{5}\left (\cos \frac{2\pi } {3} + \mathrm{i}\sin \frac{2\pi } {3}\right )\)
\(\sqrt{5}\left (\cos \frac{\pi }{3} + \mathrm{i}\sin \frac{\pi }{3}\right )\)
\(\sqrt{5}\left (\cos \frac{2\pi } {5} + \mathrm{i}\sin \frac{2\pi } {5}\right )\)
\(\sqrt{5}\left (\cos \frac{3\pi } {2} + \mathrm{i}\sin \frac{3\pi } {2}\right )\)

9000038606

Level: 
B
Find the algebraic form of the following complex number. \[ \cos \frac{\pi } {4} + \mathrm{i}\sin \frac{\pi } {4} \]
\(\frac{\sqrt{2}} {2} + \mathrm{i}\frac{\sqrt{2}} {2} \)
\(\frac{\sqrt{2}} {2} -\mathrm{i}\frac{\sqrt{2}} {2} \)
\(\frac{\sqrt{3}} {2} + \mathrm{i}\frac{\sqrt{3}} {2} \)
\(\frac{\sqrt{3}} {2} -\mathrm{i}\frac{\sqrt{3}} {2} \)

9000038901

Level: 
B
Consider the function \(f\colon y = A\cdot \sin (B\cdot x + C)\), with real nonzero parameters \(A\), \(B\) and \(C\). Which of the following operations makes the period of the function five times smaller?
Increase \(B\) by a factor \(5\).
Increase \(A\) by a factor \(5\).
Decrease \(A\) by a factor \(5\).
Decrease \(B\) by a factor \(5\).
Increase \(C\) by a factor \(5\).
Decrease \(C\) by a factor \(5\).

9000038902

Level: 
B
Consider the function \(f\colon y = A\cdot \sin (B\cdot x + C)\), with real nonzero parameters \(A\), \(B\) and \(C\). Which of the following operations makes the amplitude of the function five times bigger?
Decrease \(A\) by a factor \(5\).
Increase \(A\) by a factor \(5\).
Increase \(B\) by a factor \(5\).
Decrease \(B\) by a factor \(5\).
Increase \(C\) by a factor \(5\).
Decrease \(C\) by a factor \(5\).

9000038609

Level: 
B
Find the algebraic form of the following complex number. \[ 5\left (\cos \frac{3\pi } {4} + \mathrm{i}\sin \frac{3\pi } {4}\right ) \]
\(-\frac{5\sqrt{2}} {2} + \mathrm{i}\frac{5\sqrt{2}} {2} \)
\(\frac{5\sqrt{2}} {2} -\mathrm{i}\frac{5\sqrt{2}} {2} \)
\(\frac{5} {2} + \mathrm{i}\frac{5} {2}\)
\(\frac{5} {2} -\mathrm{i}\frac{5} {2}\)