{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

M1410202 - 2.10 SECTION 2.2 POLYNOMIAL FUNCTIONS OF HIGHER...

Info icon This preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
2.10 SECTION 2.2: POLYNOMIAL FUNCTIONS OF HIGHER DEGREE PART A: INFINITY The Harper Collins Dictionary of Mathematics defines infinity , denoted by , as “a value greater than any computable value.” The term “value” may be questionable! Likewise, negative infinity, denoted by − ∞ , is a value lesser than any computable value. Warning: and − ∞ are not numbers. They are more conceptual. We sometimes use the idea of a “point at infinity” in graphical settings. PART B: LIMITS The concept of a limit is arguably the key foundation of calculus. (It is the key topic of Chapter 2 in the Calculus I: Math 150 textbook at Mesa .) Example lim x →∞ f x ( ) = − ∞ ” is read “the limit of f x ( ) as x approaches infinity is negative infinity.” It can be rewritten as: f x ( ) → − ∞ as x → ∞ ,” which is read “ f x ( ) approaches negative infinity as x approaches infinity.” The Examples in Part C will help us understand these ideas!
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2.11 PART C: BOWLS AND SNAKES Let a represent a nonzero real number. Recall that the graphs for ax 2 , ax 4 , ax 6 , ax 8 , etc. are “bowls.” If a > 0 , then the bowls open upward . If a < 0 , then the bowls open downward . Examples The graph of f x ( ) = x 2 is on the left, and the graph of g x ( ) = x 2 is on the right. lim x →∞ f x ( ) = lim x →−∞ f x ( ) = lim x →∞ g x ( ) = − ∞ lim x →−∞ g x ( ) = − ∞
Image of page 2
2.12 Let a represent a nonzero real number. Recall that the graphs for ax 3 , ax 5 , ax 7 , ax 9 , etc. are “snakes.” If a > 0 , then the snakes rise from left to right. If a < 0 , then the snakes fall from left to right. Examples The graph of f x ( ) = x 3 is on the left, and the graph of g x ( ) = x 3 is on the right. lim x →∞ f x ( ) = lim x →−∞ f x ( ) = − ∞ lim x →∞ g x ( ) = − ∞ lim x →−∞ g x ( ) =
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2.13 PART D: THE “ZOOM OUT” DOMINANCE PROPERTY Example The graph of f x ( ) = 4 x 3 5 x 2 7 x + 2 is below. Observe that 4 x 3 is the leading (i.e., highest-degree) term of f x ( ) . If we “zoom out,” we see that the graph looks similar to the graph for 4 x 3 (in blue below).
Image of page 4