Do Now Find the following: (f + g)(-1) = (g ͦ f)(x) = (g - f)(2) = (f /g)(x) =
Even & Odd Functions
What are even & odd functions? Plug in 3 to this equation… Now plug in -3… What do you notice about the answers?
What are even & odd functions? Plug in 3 to this equation… Now plug in -3… What do you notice about the answers?
What are even & odd functions? Plug in 3 to this equation… Now plug in -3… What do you notice about the answers?
Even Functions A function is even when it is symmetric about the y-axis. Meaning when you plug in –x the function simplifies to be the same f(-x) = f(x) Examples:
Odd Functions A function is odd when it is symmetric about the origin - the point (0,0) Meaning when you plug in –x & simplify the signs of each term changes! f(-x) = - f(x) Examples:
Functions that are NEITHER A function is neither when it is NOT symmetric about the y-axis or the origin Most functions are neither even nor odd Meaning when you plug in –x you get a completely different function that is not the same & does not have all signs changed Examples:
So Basically… Plug in a negative and get Same # Different Signs Odd Plug in a negative and get a Same Number Same Sign Even
Even Functions-Graphing
Even Functions Graphing Determine which are even…
Odd Functions-Graphing
Odd Functions Graphing Determine which are odd…
Even Functions-Algebraically Plug in –x and simplify! If you get the same function, it is even! Note: If the function has all EVEN exponents and/or a constant (#) it will be even! That means it has variable exponents of 2,4,6,etc…
Odd Functions-Algebraically Plug in –x and simplify! If you get the opposite function, it is odd! Note: If the function has all ODD exponents & NO constant it will be odd! That means EVERY variable term has an exponent of 1,3,5,7,etc…
Neither Functions-Algebraically Plug in –x and simplify! If you do not get the same function, or all of the signs do not change, it is neither! Still -5 If the function has a mixture of even or odd exponents, or odd exponents & a constant then it will be neither! This is the MOST COMMON!
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Example: Determine if the function is even, odd, or neither.
Example: Determine if the function is even, odd, or neither.
Example: Determine if the function is even, odd, or neither.
Example: Determine if the function is even, odd, or neither.
Example: Determine if the function is even, odd, or neither.
Example: Determine if the function is even, odd, or neither.
Example: Determine if the function is even, odd, or neither.
Example: Determine if the function is even, odd, or neither.
NC Final Exam Question Example Which of the following is an even function?
Challenge Question Is (x+1)2 even, odd, or neither?
Challenge Question Can a function be both even and odd?
Homework Worksheet front and back! Don’t forget to Justify!!! Graphs & multiple choice questions from http://www.mathsisfun.com/algebra/functions-odd-even.html