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1.7 Even and Odd Functions Mon Sept 30. Do Now Let , Find f(-x). Quiz Review. Retakes Last day Friday Let me know today 90% of new score. Even Functions. A function is considered even if, for every x in the domain of f, f(x) = f(-x)
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1.7 Even and Odd FunctionsMon Sept 30 Do Now Let , Find f(-x)
Quiz Review • Retakes • Last day Friday • Let me know today • 90% of new score
Even Functions • A function is considered even if, for every x in the domain of f, f(x) = f(-x) • This tells us that if we plug in opposite x values, we should get the same y value • Even functions are symmetric with respect to the y-axis
Ex • Show f(x) = x^2 + 2 is even
Odd Functions • A function is considered odd if, for every x in the domain of f, f(-x) = -f(x) • This tells us if we plug in opposite x values, we should get opposite y values • Odd functions are symmetric with respect to the origin or the line y = x
Ex • Show f(x) = x^3 + x is odd
Even and odd functions • A function with variables cannot be both even and odd • Always evaluate f(x) and f(-x) and compare the two • A function can be neither even nor od
Another way • Given f(x), evaluate f(-x) and SIMPLIFY: • If you get the exact same thing, f(x) is even • If you can factor out a negative sign and get the original inside, f(x) is odd • If you can’t do either, neither
Ex • Determine whether each of the following functions is even, odd, or neither • 1) • 2)
You try • Determine whether each function is even, odd or neither • 1) • 2) • 3)
Closure • How can you determine whether a function is even, odd, or neither? • HW: p.163-164 #33-47
1.7 TransformationsTues Oct 1 • Do Now • Graph the following • 1) f(x) = x^2 • 2) g(x) = x^2 + 2 • 3) h(x) = (x + 4)^2 + 2
Transformations • A transformation is an operation on a basic function (y = x, x^2, 1/x, etc) that changes the function, but keeps the general behavior
Types of Transformations • Translations • Only moves the function • Reflections • Flips the function • Stretch/Shrink • Changes the shape of the function
Translations • Vertical Translation • For b > 0, y = f(x) + b is y = f(x) shifted up b units y = f(x) – b is y = f(x) shifted down b units • Horizontal Translation • For d > 0, y = f(x – d) is y = f(x) shifted right d units y = f(x + d) is y = f(x) shifted left d units
Ex • Graph the original function, then describe and graph the translation. • 1) f(x) = x^2 - 6 • 2) g(x) = |x – 4| • 3) h(x) = sqrt(x + 2) • 4) p(x) = (x + 2)^2 - 3
Reflections • 2 common reflections: • The graph of y = - f(x) is the reflection of y = f(x) across the x-axis • The graph of y = f(-x) is the reflection of y = f(x) across the y-axis
Ex • Let f(x) = x^3 – 4x^2. Describe how each graph can be compared to f(x) • 1) g(x) = (-x)^3 – 4(-x)^2 • 2) h(x) = 4x^2 – x^3
Vertical Stretch/Shrink • The graph of y = a f(x) will vertically affect f(x) by: • Stretching vertically if |a| > 1 • Shrink vertically if 0 < |a| < 1 • These transformations affect the y-value while keeping the x-coordinate the same
Horizontal Stretch/Shrink • The graph of y = f(cx) can be obtained from the graph of y = f(x) by: • Shrinking horizontally if |c| > 1 • Stretching horizontally if 0 < |c| < 1 • These transformations affect the x-coordinate while keeping the y-coordinate the same
Ex • Ex 6 in the book
Closure • How does each type of transformation affect the original function? • HW: p.164 #49-83 every other odd, 97-113 odds, 119-127 odds • Ch 1 Test Fri Oct 4
1.7 HW ReviewWed Oct 2 • Do Now • 1) Write an equation for a function that has the shape of y = |x|, but stretched horizontally by a factor of 2, and shifted down 5 units • 2) Write an equation for a function that has the shape of x^3, but upside-down and shifted right 5 units
Closure • When only given a graph (x,ycoordinates), how do we apply reflections, translations, and stretch/shrinks? • HW: p.169 #25-31 odds, 53 55 69 71 83-95 odds 101
Ch 1 ReviewThurs Oct 3 • Do Now • Find the domain of
Ch 1 Review • 1.1 Distance Formula and Circle Equations • 1.2 Domain and Range • 1.5 Increasing/Decreasing and Max/Mins using a calculator • 1.5 Piecewise Functions • 1.6 Compositions and Decomposing • 1.7 Even and Odd Functions • 1.7 Transformations
Closure • Which of the Ch 1 topics is most difficult for you? Why? • Ch 1 Test tomorrow!