Rational Expressions GRAPHING
Objectives Graph a rational function, find its domain, write equations for its asymptotes, and identify any holes (point discontinuity) in its graph.
Glossary Terms asymptote horizontal asymptote point discontinuity rational function vertical asymptote y-intercept
Rational Function An equation in the form Where p(x) and q(x) are polynomial functions and q(x)0.
When graphing rational functions State domain Find Vertical Asymptote(s) Find Point of Discontinuity in the graph (HOLES) Find Horizontal Asymptote Find the y-intercepts & x-intercepts Sketch
Domain: (-∞,-5) U (-5,1) U (1,∞) Vertical Asymptote(s) x=1 & x=-5 State Domain Find Vertical Asymptote(s) Find Point of Discontinuity in the graph Domain: (-∞,-5) U (-5,1) U (1,∞) Vertical Asymptote(s) x=1 & x=-5 Find Point of Discontinuity in the graph - none
H.A. y = 0 Find Horizontal Asymptote Compare the degree of the numerator to the degree of the denominator degree of the numerator < degree of the denominator H.A. y = 0
Find Horizontal Asymptote Compare the degree of the numerator to the degree of the denominator degree of the numerator < degree of the denominator H.A. y = 0 degree of the numerator = degree of the denominator H.A. y = the ratio of the lead coefficients. degree of the numerator > degree of the denominator none
Find y-intercept Substitute zero for x and find the value of the function
Sketch the graph Vertical Asymptotes Horizontal Asymptote y-intercept Plot a few points x y -10 .05 -5.5 .92 -4.5 -1.1 .5 1.5 10 .02
Domain: (-∞,-6) U (-6,-1) U (-1,∞) Vertical Asymptote(s) x=-1 4 State the domain Find Vertical Asymptote(s) Find Point of Discontinuity in the graph Domain: (-∞,-6) U (-6,-1) U (-1,∞) Vertical Asymptote(s) x=-1 Find Point of Discontinuity at -6
H.A. y = the ratio of the lead coefficients. Find Horizontal Asymptote Compare the degree of the numerator to the degree of the denominator degree of the numerator = degree of the denominator H.A. y = the ratio of the lead coefficients. y = 1
Find y-intercept Substitute zero for x and find the value of the function
Sketch the graph Vertical Asymptote Point of Discontinuity Horizontal Asymptote y-intercept Plot a few points x y -10 1.8 -2 8 -.5 -13 1 -2.5 10 .4
Vertical Asymptote(s) NONE Find Point of Discontinuity at -4 6 State the Domain Find Vertical Asymptote(s) Find Point of Discontinuity in the graph Domain: (-∞,-4) U (-4,∞) Vertical Asymptote(s) NONE Find Point of Discontinuity at -4
H.A. there is no horizontal asymptote Find Horizontal Asymptote Compare the degree of the numerator to the degree of the denominator degree of the numerator > degree of the denominator H.A. there is no horizontal asymptote
Find y-intercept Substitute zero for x and find the value of the function
Sketch the graph Point of Discontinuity y-intercept Plot a few points x y -5 -9 -3 -7 4
Homework – day 1 Rational Functions Worksheet 1, part A & B Graphing Rational Function Worksheet #1-3, 5
Graphing Rational Expressions Oblique Asymptotes To find Oblique (Slant) Asymptotes you will need to divide.
Homework – day 2 Page 405 21-43 odd