Consider the function whose formula is f(r) = √(r - 4).
What is the domain of f?
b. Use a table of values of x approaching 2 to estimate the value of lim f(x), if you think the limit exists. And if you think the limit does not exist, explain why.
c. Use algebra to simplify the expression 1 / (x - 4), and hence work to evaluate lim f(r) exactly if it exists. Or explain how your work shows the limit fails to exist. Discuss how your findings compare to your results in (b).
d. True or false: f(2) = 8. Why?