Continuous Function Math Example 3

Follow the full solution, then compare it with the other examples linked below.

Example 3

easy
Is g(x)=1xg(x) = \dfrac{1}{x} continuous on (โˆ’โˆž,โˆž)(-\infty, \infty)? If not, identify where and why.

Solution

  1. 1
    g(x)=1/xg(x) = 1/x is undefined at x=0x = 0 (division by zero), so the first condition of continuity fails there.
  2. 2
    Therefore gg is not continuous on all of R\mathbb{R}; it is discontinuous at x=0x = 0 with an infinite discontinuity (vertical asymptote).

Answer

Not continuous on (โˆ’โˆž,โˆž)(-\infty,\infty); discontinuous at x=0x=0 (infinite discontinuity)
A function cannot be continuous at a point where it is undefined. The reciprocal function has a vertical asymptote at x=0x=0, which is an infinite (essential) discontinuity โ€” it cannot be removed by redefining the function value.

About Continuous Function

A function is continuous at a point if the limit equals the function value there, with no jumps, holes, or vertical asymptotes in the interval of interest.

Learn more about Continuous Function โ†’

More Continuous Function Examples