function prob_3_2
  
close all;  

t = linspace(0,3);
y = abs(2-t.^2);
figure; plot( t, y, '-o' );

disp( 'Truth is:' );
sqrt(2)

nIters = 100;
epsilon = 0.05;
x(1) = 1.5;
for i=2:nIters,
  x(i) = x(i-1) - epsilon*fPrime(x(i-1));
end
x

figure; plot( x, 'or' );

function fp = fPrime( x )

if( x < -sqrt(2) )
  fp = 2*x;
elseif( x > +sqrt(2) )
  fp = 2*x;
else
  fp = -2*x;
end