Dap An Thi Matlab

Cau 1: a) >> % Khai bien ban dau: >> t=[0 8 14 18 22 27 38 41 50 62 66 72 76 82 93]; >> n=[0 5 30 50 100 201 502 905 1305 1508 2100 2700 3001.5 2999 3001]; >> % Ve cac diem do tren man hinh may tinh: >> plot(t,n,'s') b) >> % Phuong trinh mo ta bang so lieu khi biet dang tong quat: >> pt = polyfit(t,n,14) c) >> % Ve dac tinh mo ta so lieu ra man hinh: >> y = polyval(pt,t); >> plot(t,y,'-r') >> grid on % Hien luoi toa do. d) >> % Tim gia tri lon nhat cua toc do: >> nmax = max(y) -----------------------------------------------------cau 2: a) File/New/M-File ---> tao file gptb2.m voi noi dung sau: function gptb2 a = input('nhap gia tri a='); b = input('nhap gia tri b='); c = input('nhap gia tri c='); syms x; x = solve(a*x^2+b*x+c,'x'); x = eval(x) % convert x to real variable (from string) --------hoac : File/New/M-File ---> tao file giaipt.m voi noi dung sau: function giaipt(a,b,c) syms x; x = solve(a*x^2+b*x+c); x = eval(x) % convert x to real variable (from string) Voi truong hop cu the, tai dau nhac cua MATLAB ta go: >> giaipt(1,-3,2) ---------------------------------------------------------b) >> syms a c d e x >> f = a*x^5+c*x^2+d*x+e; >> dhb1_theo_x = diff(f,x) >> dhb1_theo_a = diff(f,a) >> dhb2_theo_a = diff(f,x,2) >> dhb2_theo_a = diff(f,a,2) ------------c) >> g =f+b*x^4; >> tpbd = int(g) >> a=1; >> b=2; >> c=-3; >> d=1; >> e=1; >> g = a*x^5 + b*x^4 + c*x^2 + d*x + e; >> tpxd = int(g,0,20) ---------------------------------------Cau 3:

a) >> a = [ 2 -3 3 -1 -1; -1 2 2 -2 -1; 4 -1 2 -3 -1; 3 3 1 -2 1; 1 2 -3 -1 -1]; >> b = [0;0;1;6;-2]; x = a\b b) >> [x,y,z] = solve('x^2*y + x*y + z = 3','x*y^2-x*y-z = -1','x*y-x*y*z+z = 1') ----------------------------------------Cau 4: a) omega = 0.1:0.05:2*pi; s = j*omega; r = 1./7.373./s; o = 1.6.*exp(-0.12.*s)./(0.663.*s+1).^3; Wh = r.*o; re = real (Wh); im = imag (Wh); plot(re,im,'r-') ------b) >> r = tf(1,[7.373 0]); >> [num,den] = pade(0.12,5); % xap xi thoi gian tre. >> o = zpk([],[-1/0.663,-1/0.663,-1/0.663],1.6)*tf(num,den); >> Wh = r*o; >> Wk = feedback(Wh,1); >> nyquist(Wh) % Ve dac tinh tan so bien do pha cua he ho. >> step(Wk) % Ve dac tinh qua do cua he kin. >> grid on >> hold on ----------------------------------------------Cau 5: function cau5 cau5.m disp('Nhap so diem tung mon hoc ki truoc:'); a=input('diem mon ATNL='); b=input('diem mon Chuyen de='); c=input('diem mon THUD='); d=input('diem mon HQNL='); disp('nhap so hoc trinh cua tung mon:'); ta=input('so hoc trinh mon ATNL='); tb=input('so hoc trinh mon Chuyen de='); tc=input('so hoc trinh mon THUD='); td=input('so hoc trinh mon HQNL='); x = a*ta + b*tb + c*tc + d*td; y = ta + tb + tc + tc; disp(' Diem trung binh hoc ky = ') dtb = x/y % diem trung binh hoc ky diem = [a b c d]; disp('mon hoc co diem cao nhat = ') dcn = max(diem) disp('Mon hoc co diem thap nhat = ') dtn = min(diem) % mon hoc co diem thap nhat -------------------------------------------------Cau 6: function cau6 cau6.m tvtb=input('Nhiet do dau vao tuabin tvtb = '); if tvtb<440 disp('Bo dieu chinh hoi qua nhiet phai cai tao lai!');

elseif tvtb>455 disp('Bo dieu chinh hoi qua nhiet phai cai tao lai!'); elseif tvtb>=440 & tvtb<445 disp('Bo dieu chinh lam viec chap nhan duoc!'); else disp('Bo dieu chinh lam viec tot!'); end >> cau6 Nhiet do dau vao tuabin tvtb = 450 Bo dieu chinh lam viec tot ----------------------------------------------------Cau 7: >> syms x >> f = x^8 - x^6 + x^5 - 3*x^4 - x^2 - 6*x + 1; % Tim cac diem khong cua ham so: >> x = solve(f) % Tim gia tri cuc tieu cua ham so trong khoang [0.2, 1.5]: >> f = inline('x^8 - x^6 + x^5 - 3*x^4 - x^2 - 6*x + 1'); >> xmin = fminbnd(f,0.2,1.5) -------------------------------------------------------Cau 8: File/New/M-File ---> tao file function8.m voi noi dung sau: function f=funtion8(x) %function8.m f = [2*x(1)^4 + x(2)^4 - 2*x(1)^2 - 2*x(2)^2 + 4*sin(x(1)*x(2))]; % Go lenh trong cua so MATLAB: >> a = [1 -1; 0 -1]; >> b = [0;-1]; >> options = optimset('fmincon'); >> options = optimset(options,'Display','final','LargeScale','off'); >> x0 = [2 0]; >> % Gia tri nho nhat cua ham fval tai x(1) v� x(2): >> [x,fval] = fmincon('function8',x0,a,b,[],[],[],[],[],options) ----------------------------------------------------------http://www.kaspersky.com/kos/eng/partner/default/kavwebscan.html