A = [ 3 4 5 ; 6 7 8 ; 9  10  11 ; 12 13 14 ]
size(A)
B = [ 1 2 3]'
size(B)
A*B
size(A*B)


length(A*B)

C = rand(5,3,4,7)
size(C)
length(C)


D=round(rand(3,4)*100)
max(D')
min(D')

max(D(:))

D(2,1)
D(2)


E = 25:35

sqrt(sum(E.*E))


pinv(D)*D

D*pinv(D)

%prod

%sum

x= -5*pi : 5*pi 
y = cos(x)
plot(y)

x=[0:0.01:10];
y=cos(x);
plot(x,y), xlabel('x'), ylabel('cos(x)');

figure(1)
fplot('exp(-2*t)*sin(t)',[0, 4]);
figure(2)
t = 0:.1:4
y = exp(-2*t).*sin(t);
plot(t,y)

figure(3)
x = [0:0.01:5];
y = exp(-1.5*x).*sin(5*x+3);
plot(x,y)% , axis([0 5 min(y) max(y)])


[x,y] = meshgrid(-5:1:5,-3:1:3)


x = solve('x + 3 = 0')

x = solve('x+8')


s = solve('x^2 -6*x -12 = 0')


syms w
q = sym('q')

denk = 3*w^2 + 5*w - 15 

solve(denk)

hold on




eq1 = 'w + x + 4*y + 3*z = 5';
eq2 = '2*w +3*x+y-2*z = 1';
eq3 = 'w + 2*x-5*y+4*z = 3';
eq4 = 'w - 3*z = 9';

s = solve(eq1,eq2,eq3,eq4);

syms w
simplify(cos(w)^2+sin(w)^2)

syms x
kok = solve('e^x-x^2=0')
isreal(kok)

isempty

isnan





