好好好

%% 第一题 % （1） x = -2:0.001:2; y = x.*sin(1./x); plot(x,y); xlabel('x') ylabel('y') title('plot画的图像'); figure fplot(@(z)z*sin(1./z),[-2 2]); xlabel('x') ylabel('y') title('fplot画的图像'); %(2) syms m; f=m*sin(1/m); disp('xsin(1/x)的极限为：'); L=limit(f, m, 0) %% 第二题 A = [4 2 -1 3 -1 2 12 3 0]; B = [2;10;8]; disp('方程组的解为：'); x = inv(A)*B %% 第三题 % 对sin（x）进行多次求导，并画图查看 syms x1 y = sin(x1); y1 = diff(y,x1); y2 = diff(y1,x1); y3 = diff(y2,x1); y4 = diff(y3,x1); y5 = diff(y4,x1); y6 = diff(y5,x1); y7 = diff(y6,x1); y8 = diff(y7,x1); figure subplot(411) ezplot(y,[-4*pi :0.01:4*pi]); subplot(412) ezplot(y1,[-4*pi :0.01:4*pi]); subplot(413) ezplot(y2,[-4*pi :0.01:4*pi]); subplot(414) ezplot(y3,[-4*pi :0.01:4*pi]); figure subplot(411) ezplot(y4,[-4*pi :0.01:4*pi]); subplot(412) ezplot(y6,[-4*pi :0.01:4*pi]); subplot(413) ezplot(y7,[-4*pi :0.01:4*pi]); subplot(414) ezplot(y8,[-4*pi :0.01:4*pi]); %% 第五题 A = [1 0 0 -1 0 0 0 1 0 0 -1 0 0 0 1 0 0 -1]; intcon = [1 2 3 ]; B = [200;-100;150;-80;100;-50]; f = [200 150 180]; [x fval exitflag] = intlinprog(f,intcon,A,B); disp('产品A B C分别产量为：'); disp(x); disp('总利润为：'); disp(fval);