Algebra Maximum and minimum.
posted by Niki .
I don't understand how to find the maximum and minimum.
Determine whether the given quadratic function has a minimum value or maximum value. Then find the coordinates of the minimum or maximum point.
15.f(x) = x2 + 2x  4
20.f(x) = 2x2  4x
19.f(x) = x2  2x + 1
30.f(x) = 3x2  3x

#15 and #30 open downwards, so they have a maximum
#20 and #19 open upwards, so they have a minimum.
change the equations to the form
f(x) = a(xh)^2 + k by completing the square
You should have learned how to do this, and read the vertex from that form. 
what are the maximum value and minimum value of (x)=12sin(2x2pi/3)5l+3

2x2 16x+4= i do not know

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