Difference between revisions of "Week2a"

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[[Media:Linear-fns.pdf|Handout on linear functions]]
 
[[Media:Linear-fns.pdf|Handout on linear functions]]
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[[Media:Quadratic-fns.pdf|Handout on quadratic functions]]
 
[[Media:Quadratic-fns.pdf|Handout on quadratic functions]]
 
   
 
   
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Consider the following table of function values for $f(x)$ and $g(x)$.  
 
Consider the following table of function values for $f(x)$ and $g(x)$.  
  
[[File:function-values.jpg|300px]]
+
[[File:function-values.jpg|250px]]
  
 
a) Evaluate: $(f+g)(4)$, $\dfrac{f}{g}(3)$, $\dfrac{g}{f}(3)$, $(f\cdot g)(5)$, $(f\circ g)(5)$, $(g\circ f)(2)$, $f^{-1}(-3)$, $g^{-1}(8)$.
 
a) Evaluate: $(f+g)(4)$, $\dfrac{f}{g}(3)$, $\dfrac{g}{f}(3)$, $(f\cdot g)(5)$, $(f\circ g)(5)$, $(g\circ f)(2)$, $f^{-1}(-3)$, $g^{-1}(8)$.

Revision as of 15:05, 3 November 2014

Handouts

Handout on linear functions

Handout on quadratic functions


Activities

Activity: working with linear functions.

The temperature scales Celsius and Fahrenheit have a linear relationship with $0^{\circ}C = 32^{\circ}F$ and $100^{\circ}C = 212^{\circ}F$.

  1. Write a linear equation expressing $F$ in terms of $C$ and sketch its graph.
  2. If it is $75^{\circ}C$, what is the temperature in $F$?
  3. If it is $75^{\circ}F$, what is the temperature in $C$?
  4. What about if it is $175^{\circ}F$?
  5. What about if it is $-25^{\circ}F$?
  6. Did you compute each $C$ in parts (3) - (5) separately? Could you have avoided this?
  7. Graph the line $F=C$ on the same axes. Can you tell from your graph if there a temperature $x$ for which $x^{\circ}C=x^{\circ}F$? If so, what is $x$?


Activity: working with quadratic functions.

The revenue of Miley Cyrus' concert in Vancouver depends on the number of unsold seats. Miley's manager calculates that the revenue is given by $R(x) = 8000+70x-x^2$, where $x$ is the number of unsold seats. Find the maximum revenue and the number of unsold seats that corresponds to maximum revenue.


Activity: working with general functions.

Consider the following table of function values for $f(x)$ and $g(x)$.

Function-values.jpg

a) Evaluate: $(f+g)(4)$, $\dfrac{f}{g}(3)$, $\dfrac{g}{f}(3)$, $(f\cdot g)(5)$, $(f\circ g)(5)$, $(g\circ f)(2)$, $f^{-1}(-3)$, $g^{-1}(8)$.

b) Suppose $f$ is even and $g$ is odd. Evaluate $f(-3)$ and $g(-5)$.


Extra discussion questions

  1. Find the number $c$ such that $x^2+5x+c$ is a perfect square for all $x$ values.
  2. Determine the $x$-values for which $x^2+4x+1\geq 1$.
  3. What are the $x$-intercepts of $y=x^2-4x+5$? Justify your answer.