How do you find the vertex of the parabola #y=2x^2-8x+7#?
2 Answers
You can find the coordinates of your vertex either using a mnemonic or the derivative:
1) Mnemonic: the coordinates of the vertex of a parabola in the form:
in your case:
2) Derivative: determine the derivative of your function and set it equal to zero:
substituting back in your function:
Graphically:
graph{2x^2-8x+7 [-4.385, 4.386, -2.19, 2.193]}
A slight variant on method
Explanation:
Given:
Write as:
Consider the
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Substitute
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