Posted by Niki on .
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

Algebra Maximum and minimum. 
Reiny,
#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. 
Algebra Maximum and minimum. 
jones,
what are the maximum value and minimum value of (x)=12sin(2x2pi/3)5l+3

Algebra Maximum and minimum. 
butt face,
2x2 16x+4= i do not know

Algebra Maximum and minimum. 
Anonymous,
Find the minimum and maximum possible areas of a rectangle measuring 2 km by 5 km.