Understanding graph transformations helps us see how the shape and position of a graph can change based on its original form.
Types of Transformations
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Translations:
- Vertical Shift: When we add or subtract a number (let's call it k) to the function, it moves the graph up if we add, and down if we subtract. So, the new function looks like f(x)+k.
- Horizontal Shift: When we change the input of the function by subtracting or adding a number (let's call it h), the graph moves left if we subtract and right if we add. This looks like f(x−h).
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Reflections:
- Across the x-axis: If we multiply the function by -1, like this: −f(x), it flips the graph upside down.
- Across the y-axis: If we switch the x's to negative, like this: f(−x), it flips the graph side to side.
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Stretches:
- Vertical Stretch/Compression: If we multiply the function by a number (let's call it a), it stretches the graph taller if ∣a∣>1 and makes it shorter if 0<∣a∣<1. So, it looks like a⋅f(x).
- Horizontal Stretch/Compression: If we change the 'x' in the function by multiplying it by a number (let's call it b), it makes the graph wider if ∣b∣<1 and skinnier if ∣b∣>1. This can be written as f(bx).
By using these transformations step by step, we can draw the graph of any function by starting with its original or "parent" graph.