csat-suneung 2013 Q20

csat-suneung · South-Korea · csat__math-humanities 4 marks Curve Sketching Multi-Statement Verification (Remarks/Options)
For the two functions $$f(x) = \begin{cases} -1 & (|x| \geq 1) \\ 1 & (|x| < 1) \end{cases}, \quad g(x) = \begin{cases} 1 & (|x| \geq 1) \\ -x & (|x| < 1) \end{cases}$$ which of the following statements are correct? Choose all that apply from $\langle$Remarks$\rangle$. [4 points]
Remarks ᄀ. $\lim_{x \rightarrow 1} f(x)g(x) = -1$ ㄴ. The function $g(x+1)$ is continuous at $x = 0$. ㄷ. The function $f(x)g(x+1)$ is continuous at $x = -1$.
(1) ᄀ
(2) ㄴ
(3) ᄀ, ㄴ
(4) ᄀ, ㄷ
(5) ᄀ, ㄴ, ㄷ
For the two functions
$$f(x) = \begin{cases} -1 & (|x| \geq 1) \\ 1 & (|x| < 1) \end{cases}, \quad g(x) = \begin{cases} 1 & (|x| \geq 1) \\ -x & (|x| < 1) \end{cases}$$
which of the following statements are correct? Choose all that apply from $\langle$Remarks$\rangle$. [4 points]

\textbf{Remarks}\\
ᄀ. $\lim_{x \rightarrow 1} f(x)g(x) = -1$\\
ㄴ. The function $g(x+1)$ is continuous at $x = 0$.\\
ㄷ. The function $f(x)g(x+1)$ is continuous at $x = -1$.\\
(1) ᄀ\\
(2) ㄴ\\
(3) ᄀ, ㄴ\\
(4) ᄀ, ㄷ\\
(5) ᄀ, ㄴ, ㄷ