194
2 - uni fun1.m nom bilan saqlash
3 – kamandalar oynasida ishlash:
>>fplot@fun1[0, 10] % fun1 funksiyaning
grafigini kesmada qurish
>> grid on ;
>>
x1=fzero@fun1,[0
1 ]
% funksiyaning [0 1] kesmadagi nollarini
hisoblash
X1 =
0.8905
>> x2=fzero@fun1,[2 3]
% funksiyaning [0 1] kesmadagi nollarini hisoblash
X2 =
2.8500
>> x3=fzero@fun1,[1, 5, 0.001]
% funksiyaning [0 1] kesmadagi nollarini hisoblash
X3 =
5.8128
Tenglamalarni yechish
1-misol. sin(x
2
-0.6) = 0 tenglamani [0; 3 ]kesmada yeching.
1. Grafig usul:
>> x=0: 01:3;
% argumentning qiymati
>> f=sin(x
^
2-0.6);
% funksiyaning qiymati
>> plot(x,[f,0*f])
% y=f va y=0 funkiyaning grafiglari
>> grid on ;
>> x1 = ginput
% nuqtaning koordinatalarini ekranga enteraktiv….
Chiqarish (sichqonchaning ko’rsatkichlarini kerakli nuqtaga olib kelinadi..
va
u bosib turilgan holda<
> tugmasi bosiladi)
x1 =
0.7746
-0.0012
%ikkinchi son y10 ga mos keladi
>> g2=ginput
X2 =
1.9343
0.0023
>> x3=fzero(f,[2 3])
X3 =
2.6326
2. Analitek usul;
>> X = 0:,01:3;
195
%argumentning qiymatlari
>> n =length(x);
% x vectorning uzunligini xisoblash
>> ind=1 : n-1;
% indekslar vectori
>> f=sin(x.^2-0.6);
%funksiyaning qiymati
>> ildizlar=x (f(ind). *f(ind+1)<=0)
%funksiya
qo`shni
qiymatlarining
ko’paytmasi
manfiy
bo’lgan
nuqtalar
tenglamalarning ildizlari bo’ladi va ular ildizlar vektoriga o’tadi .
Ildizlar=0.7746 1. 9300 2.6200
2-misol.
2x+y -5z +t= 8
x – 3y -6t = 9
2y – z + 2t = -5
x + 4y -7z + 6t= 0
Tenglamalar sistemasini yeching.
Yechish.
>> A=[2 1-5 1;1-3 0 -6; 0 2 -1 2;1 4 -7 6];
%sistemaning matritsasi
>> B=[8;9;-5;0];
%o’ng tomonning ustun vektori
>> A1=[A,B];
%sistemaning kengaytirilgan matritsasi
>> if and(rank(A)==rank(A1),rank(A)==4)
%matritsa rangini tekshirish
disp (‘Sistema yagona yechimga ega’);
x=A\B;
% teskari slesh yoki chapdan bo’luv – chiziqli sistemani….
%Gauss usuli bilan yechish
x1=x’;
End
x1
x1=
3.0000
-4.0000 -1.000 1.0000
>>x=A^(-1)*B; x2=x’
%A\B yozuvning ikkinchi varianti
x2 =
3.0000
-4.0000 -1.0000 1.0000
>>inv(A)*B; x3=x’
%A\B yozuvning uchunchi varianti
x2 =
