1003085505

Level: 
Project ID: 
1003085505
Accepted: 
1
Clonable: 
0
Easy: 
1
Decide which of the following functions have points of discontinuity. \[ \begin{aligned} f_1(x)&=\frac{x-1}{x^2+1} \\ f_2(x)&=\frac{x^2-1}{x+1} \\ f_3(x)&=\frac{3x-1}{x^3+1} \\ f_4(x)&=\frac{x+1}{x^2-x+1} \end{aligned} \] The only such functions are:
\( f_2 \), \( f_3 \)
\( f_1 \), \( f_2 \), \( f_3 \)
\( f_2 \), \( f_3 \), \( f_4 \)
\( f_2 \), \( f_4 \)