Sine, Cosine, Tangent, and Cotangent

1003076504

Level: 
B
Choose the false statement:
The function \( f(x)= \mathrm{tg}\,x \) is even.
The function \( f(x)=\mathrm{cotg}\,x \) is decreasing on the interval \( (0;\pi) \).
The function \( f(x)=\sin x \) is bounded on its domain.
The values of function \( f(x)=\cos x \) always lie between \( -1 \) and \( 1 \).

1103082703

Level: 
C
Function \( f \) is given completely by the next graph. Identify which of the following statements is true.
\( f(x)=-|\sin x|;\ x\in[-2\pi;2\pi] \)
\( f(x)=|\cos x|;\ x\in[-2\pi;2\pi] \)
\( f(x)=|-\sin x|;\ x\in[-2\pi;2\pi] \)
\( f(x)=-0.5\cdot\sin x;\ x\in[-2\pi;2\pi] \)

9000038910

Level: 
B
Consider the function \(f\colon y =\mathop{\mathrm{cotg}}\nolimits x\). In the following list identify the function which has the same graph as the graph of the function \(f\).
\(k\colon y = -\mathop{\mathrm{tg}}\nolimits \left (x + \frac{\pi } {2}\right )\)
\(g\colon y = -\mathop{\mathrm{tg}}\nolimits x\)
\(b\colon y =\mathop{\mathrm{tg}}\nolimits \left (x + \frac{\pi } {2}\right )\)
\(h\colon y =\mathop{\mathrm{tg}}\nolimits \left (x - \frac{\pi } {2}\right )\)
\(m\colon y = -\mathop{\mathrm{tg}}\nolimits x - \frac{\pi } {2}\)

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 \(5\).