130 likes | 644 Views
Limits Involving Infinity. Section 2.2a. Limits Involving Infinity. Note: “Infinity” does not represent a real number……however,. We can say “the limit of f as x approaches infinity,” meaning the limit of f as x moves increasingly far to the right on the number line, or….
E N D
Limits Involving Infinity Section 2.2a
Limits Involving Infinity Note: “Infinity” does not represent a real number……however, We can say “the limit of f as x approaches infinity,” meaning the limit of f as x moves increasingly far to the right on the number line, or… Saying “the limit of f as xapproaches negative infinity” means the limit of f as xmoves increasingly far to the left.
Limits Involving Infinity The graph of the reciprocal function: Our new limits: The line y = 0 is a horizontal asymptote of the graph of f…
Definition: Horizontal Asymptote The line y = b is a horizontal asymptote of the graph of a function y = f(x) if either or Ex: Find any H.A. of the graph of H.A.: y = 2
Definition: Horizontal Asymptote The line y = b is a horizontal asymptote of the graph of a function y = f(x) if either or Ex: Find any H.A. of the graph of Investigate with both a graph and a table… H.A.: y = –1, y = 1
Sandwich Theorem Revisited Find for First, what do the graph and table suggest??? Confirm Analytically: For x > 0, we have And by the Sandwich Theorem:
Limits Involving Infinity Properties of Our New Limits: Note: All of the properties for limits approaching real numbers also hold for limits approaching infinity!!! Including Sum Rule, Difference Rule, Product Rule, Constant Multiple Rule, Quotient Rule, Power Rule
Limits Involving Infinity Rewrite: Find
Limits Involving Infinity Sometimes, a function outgrows all bounds (either positive or negative) as xapproaches a finite number a we write: or Think back to the reciprocal function: and The line x = 0 is a vertical asymptote of the graph of f…
Definition: Vertical Asymptote The line x = a is a vertical asymptote of the graph of a function y = f(x) if either or
Limits Involving Infinity For the given function, (a) find the vertical asymptotes; (b) describe the behavior of the function to the left and right of each V.A. Now, check the graph! V.A.: