4.5 
Graphs of 
Tangent, 
Cotangent, 
Secant, and 
Cosecant 
Copyright © 2011 Pearson, Inc.
What you’ll learn about 
 The Tangent Function 
 The Cotangent Function 
 The Secant Function 
 The Cosecant Function 
… and why 
This will give us functions for the remaining 
trigonometric ratios. 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 2
Asymptotes of the Tangent Function 
 
2 
3 
2 
 
3 
2 
 
 
2 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 3
Zeros of the Tangent Function 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 4
Asymptotes of the Cotangent Function 
  0 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 5
Zeros of the Cotangent Function 
 
2 
3 
2 
 
3 
2 
 
 
2 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 6
The Secant Function 
 
2 
3 
2 
 
3 
2 
 
 
2 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 7
The Cosecant Function 
 0  
Copyright © 2011 Pearson, Inc. Slide 4.5 - 8
Basic Trigonometry Functions 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 9
Basic Trigonometry Functions 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 10
Example Solving a Trigonometric 
Equation Graphically 
Find the smallest possible number x such that x2  csc x. 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 11
Example Solving a Trigonometric 
Equation Graphically 
Find the smallest possible number x such that x2  csc x. 
The graphs of y  2  x2 and 
y  sec x are shown. 
Using the grapher, we find 
that the smallest positive 
x-coordinate where the graphs 
intersect is x  0.7749 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 12
Quick Review 
State the period of the function. 
1. y  cos 4x 
2. y  sin 
1 
4 
x 
Find the zeros and the vertical asymptotes of the function. 
3. y  
x 1 
x 1 
4. y  
x 1 
x  2x  3 
5. Tell whether y  x2  4 is odd, even, or neither. 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 13
Quick Review Solutions 
State the period of the function. 
1. y  cos 4x  /2 
2. y  sin 
1 
4 
x 8 
Find the zeros and the vertical asymptotes of the function. 
3. y  
x 1 
x 1 
1; x  1 
4. y  
x 1 
x  2x  3 
1; x  3, x  2 
5. Tell whether y  x2  4 is odd, even, or neither. even 
Copyright © 2011 Pearson, Inc. Slide 4.5 - 14

Unit 4.5

  • 1.
    4.5 Graphs of Tangent, Cotangent, Secant, and Cosecant Copyright © 2011 Pearson, Inc.
  • 2.
    What you’ll learnabout  The Tangent Function  The Cotangent Function  The Secant Function  The Cosecant Function … and why This will give us functions for the remaining trigonometric ratios. Copyright © 2011 Pearson, Inc. Slide 4.5 - 2
  • 3.
    Asymptotes of theTangent Function  2 3 2  3 2   2 Copyright © 2011 Pearson, Inc. Slide 4.5 - 3
  • 4.
    Zeros of theTangent Function Copyright © 2011 Pearson, Inc. Slide 4.5 - 4
  • 5.
    Asymptotes of theCotangent Function   0 Copyright © 2011 Pearson, Inc. Slide 4.5 - 5
  • 6.
    Zeros of theCotangent Function  2 3 2  3 2   2 Copyright © 2011 Pearson, Inc. Slide 4.5 - 6
  • 7.
    The Secant Function  2 3 2  3 2   2 Copyright © 2011 Pearson, Inc. Slide 4.5 - 7
  • 8.
    The Cosecant Function  0  Copyright © 2011 Pearson, Inc. Slide 4.5 - 8
  • 9.
    Basic Trigonometry Functions Copyright © 2011 Pearson, Inc. Slide 4.5 - 9
  • 10.
    Basic Trigonometry Functions Copyright © 2011 Pearson, Inc. Slide 4.5 - 10
  • 11.
    Example Solving aTrigonometric Equation Graphically Find the smallest possible number x such that x2  csc x. Copyright © 2011 Pearson, Inc. Slide 4.5 - 11
  • 12.
    Example Solving aTrigonometric Equation Graphically Find the smallest possible number x such that x2  csc x. The graphs of y  2  x2 and y  sec x are shown. Using the grapher, we find that the smallest positive x-coordinate where the graphs intersect is x  0.7749 Copyright © 2011 Pearson, Inc. Slide 4.5 - 12
  • 13.
    Quick Review Statethe period of the function. 1. y  cos 4x 2. y  sin 1 4 x Find the zeros and the vertical asymptotes of the function. 3. y  x 1 x 1 4. y  x 1 x  2x  3 5. Tell whether y  x2  4 is odd, even, or neither. Copyright © 2011 Pearson, Inc. Slide 4.5 - 13
  • 14.
    Quick Review Solutions State the period of the function. 1. y  cos 4x  /2 2. y  sin 1 4 x 8 Find the zeros and the vertical asymptotes of the function. 3. y  x 1 x 1 1; x  1 4. y  x 1 x  2x  3 1; x  3, x  2 5. Tell whether y  x2  4 is odd, even, or neither. even Copyright © 2011 Pearson, Inc. Slide 4.5 - 14