Is​ f(x) continuous at x equals 4​? Why or why​ not? A. ​No, f(x) is not continuous at x equals 4 because ModifyingBelow lim With x right arrow 4 f (x )does not exist. B. ​Yes, f(x) is continuous at x equals 4 because f (4 )exists. C. ​No, f(x) is not continuous at x equals 4 because f (4 )is undefined. D. ​Yes, f(x) is continuous at x equals 4 because ModifyingBelow lim With x right arrow 4 f (x )equals f (4 ).

Respuesta :

Corrected Question

Is the function given by:

[tex]f(x)=\left\{\begin{array}{ccc}\frac{1}{4}x+1 &x\leq 4\\4x-11&x>4\end{array}\right[/tex] ​

continuous at x=4​? Why or why​ not? Choose the correct answer below.

Answer:

(D) ​Yes, f(x) is continuous at x = 4 because [tex]Lim_{x \to 4}f(x)=f(4)[/tex]

Step-by-step explanation:

Given the function:

[tex]f(x)=\left\{\begin{array}{ccc}\frac{1}{4}x+1 &x\leq 4\\4x-11&x>4\end{array}\right[/tex]

A function to be continuous  at some value c in its domain if the following condition holds:

  • f(c) exists and is defined.
  • [tex]Lim_{x \to c}$ f(x)[/tex] exists.
  • [tex]f(c)=Lim_{x \to c}$ f(x)[/tex]

At x=4

  • [tex]f(4)=\dfrac{1}{4}*4+1=2[/tex]
  • [tex]Lim_{x \to 4}f(x)=2[/tex]

Therefore: [tex]Lim_{x \to 4}f(x)=f(4)=2[/tex]

By the above, the function satisfies the condition for continuity.

The correct option is D.