2. 6 Limits at Infinity; Horizontal Asymptotes: In this section, we let x become arbitrarily large (pos. or neg. ), and see what happens to f (x). What happens to the graph of f(x) as x goes to ∞ or -∞?
no y=0 a b
limits w/regard to vertical asymptotes: limits w/regards to horizontal asymptotes: EX #1: Find the infinite limits, limits at infinity, and asymptotes for the function f whose graph is shown below. 4 -1
Using previous properties, break the limit into parts. 1 Using horizontal asymptote properties. The leading powers are equal. HA y = 2/1
Using horizontal asymptote properties. Top power < Bottom power. HA y = 0 Using horizontal asymptote properties. The leading powers are equal. HA y = 2/3 Using horizontal asymptote properties. Top power > Bottom power. No HA
Divide the top and bottom by the x with the largest power from the bottom.
Rational ______functions will have _____ limit as x +∞ and x -∞ (H. A. ) SAME But what if NOT rational? ? ? . .
TWO Radical functions can have _________ horizontal asymptotes/limits!!
Think Conjugates
Polynomial NEVER Find Left and Right hand behaviors.
False statement…x must approach a constant. From Sect 2. 3.
EX #5 Evaluate.
Basic exponential function has a HA at y = 0.
= DNE Sine oscillates between 1 and -1 infinitely often, so we don’t approach any definite number.