In the xy-plane, the graph of the equation above assumes its maximum value at . What is the value of b?
We have a quadratic equation (X to the 2nd). The X coordinate of the vertex (where the quadratic equation obtained its max or min value) is determined by X=(-b)/(2a) where b is the number coefficient of the X and a is the number coefficient of the X^2
b=? a=(-2) and we know X=2
plugging in we have: 2=(-b)/[2*(-2)]
You can also use your TI calculator to plug numbers in and find, using the min/max functions which value satisfies the conditions – but this is much more difficult.
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