Question 92922
What is the range for the function

y=-2x^2+4x
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It's a parabola opening downward so you have to find the vertex
or use x=-b/2a to find the x-coordinate of the vertex and then
the corresponding y-value.
x = -b/2a = -4/(2*-2) = 1
f(1) = -2+4 = 2
So the range is " all Real Numbers less than of equal to 2".
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{{{graph(400,300,-10,10,-20,10,-2x^2+4x)}}}
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Cheers,
Stan H.