% 练习2第1-4题
% 1
A=[6,9,3;2,7,5];
B=[2,4,1;4,6,8];
A+B
A*B
A*B'

% 2
clear
A=[3,2,0,1,5];
roots(A)

% 3
clear
A = [4,9,2;7,6,4;3,5,7];
B = [37;26;28];
A\B

% 4
syms x
f = 3*x^4-12*x^3-5*x+9;
int (f,x)
diff(f,x)
int(f,x,0,2)