clc
clear
f = @(x) 20*x.^2 - 200*x +3
x= linespace(0,10,100)
y= f(x)
plot(x,y)

xlabel('x')
ylabel('f(x)')
title(plot of 20x^2 - 200x +3)
xmin = fminbnd(f,0,10)
xminf_min = f(xmin)