task_4_2

fun=@(x) ( atan(x) - 2 - (x+3).^3);
x1 = fminsearch(fun, -100) %

funABS = @(x) (abs( atan(x) - 2 - (x+3).^3));
x0 = fminsearch(funABS, -100);

start = fix(x0) - 10
finish = fix(x0) + 10
x = (start:0.01:finish)';
yyy = fun(x)
fun(x0)

figure(1)
hold('on');
plot(x,yyy,'r*');
plot(x0,fun(x0), 'b*')