minimi 

(* cerca minimo funzione iniziando da x=-3 *)
(* calcola valori funzione da -3 a 3 per verifica*)

x=.
y=x^2+2x-1;
FindMinimum[y,{x,-3}]
For[x=-3,x<=3,Print[x,"\t",y];x++](* Shift-Enter*)

{-2., {x -> -1.}}
;[o]
{-2., {x -> -1.}}

(* cerca minimo sinusoide iniziando da 0 *)
(* verifica calcolando valori da 0 a 360 *)
x=.
y=Sin[x Degree];
FindMinimum[y,{x,0}]
For[x=0,x<=315,x=x+45;Print[x,"\t",N[y,3]]](*S-E*)

{-0.999999999999999993, {x -> -89.99999978515617555}}
;[o]
{-1., {x -> -90.}}

x=.
FindMinimum[x Cos[x],{x,0.5}]  (* da 0.5 in poi *)
FindMinimum[x Cos[x],{x,1}]    (* da 1 in poi   *)
FindMinimum[x Cos[x],{x,2}]    (* da 2 in poi   *)
FindMinimum[x Cos[x],{x,10}]   (* da 10 in poi  *)
FindMinimum[x Cos[x],{x,0,-1,10}] (* da -1 a 10 inizio 0 *)
FindMinimum[x Cos[x],{x,2,1,10}]  (* da 1 a 10 inizio 2  *)
FindMinimum[x Cos[x],{x,5,3,12}]  (* da 3 a 12 inizio 5  *)
{-0.5610963381910450673, {x -> -0.8603335894802594852}}
;[o]
{-0.561096, {x -> -0.860334}}

{-3.288371395590896486, {x -> 3.425618459481331111}}
;[o]
{-3.28837, {x -> 3.42562}}

{-3.288371395590896486, {x -> 3.425618459481717091}}
;[o]
{-3.28837, {x -> 3.42562}}

{-9.477294259479793848, {x -> 9.529334405358849215}}
;[o]
{-9.47729, {x -> 9.52933}}

{-0.5610963381910450675, {x -> -0.8603335887947812425}}
;[o]
{-0.561096, {x -> -0.860334}}

{-3.288371395590896486, {x -> 3.425618459481717091}}
;[o]
{-3.28837, {x -> 3.42562}}

{-3.288371395590896486, {x -> 3.425618459074972866}}
;[o]
{-3.28837, {x -> 3.42562}}

For[x=-2,x<=12,x++;Print[x,"\t",x N[Cos[x]]]]

-1	-0.540302
0	0
1	0.540302
2	-0.832294
3	-2.96998
4	-2.61457
5	1.41831
6	5.76102
7	5.27732
8	-1.164
9	-8.20017
10	-8.39072
11	0.0486827
12	10.1262
13	11.7968

torna a inizio