Sine, cosine, tangent and cotangent

1103082703

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

2010016404

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

2010016806

Level: 
C
The domain of the expression \( \frac{\cos⁡^2 x}{1+\sin ⁡x} \) is the set:
\( \left\{x\in\mathbb{R}\colon x\neq\frac{3\pi}2 + 2k\pi,\ k\in\mathbb{Z} \right\} \)
\( \mathbb{R}\)
\( \left\{x\in\mathbb{R}\colon x\neq\frac{\pi}2 + 2k\pi,\ k\in\mathbb{Z} \right\} \)
\( \left\{x\in\mathbb{R}\colon x\neq \pi + 2k\pi,\ k\in\mathbb{Z} \right\} \)