1、练习 2.1画出下列常见曲线的图形(其中 a=1,b=2,c=3).1.立方抛物线 ;3xy解: syms x yezplot(y-x(1/3)xyy-x1/3 = 0-6 -4 -2 0 2 4 6-6-4-202462.高斯曲线 .2xey解: syms x yezplot(y-exp(-x2)xyy-exp(-x2) = 0-6 -4 -2 0 2 4 6-6-4-202463.笛卡尔曲线 , ( ).213tax2tyaxy33解: syms x y f=x3+y3-3*x*y; ezplot(f)xyx3+y3-3 x y = 0-6 -4 -2 0 2 4 6-6-4-202464
2、.蔓叶线 , ( ).21tax23tyay3解: syms x y f=y2-(x3/(1-x); ezplot(f)xyy2-x3/(1-x) = 0-6 -4 -2 0 2 4 6-6-4-202465.摆线 .)cos1(),sin(tbytax解: t=0:0.1:2*pi;x=(t-sin(t);y=2*(1-cos(t);plot(x,y)0 1 2 3 4 5 6 700.511.522.533.546.星形线 ( ).taytx33sin,co322ayx解: syms x y f=x(2/3)+y(2/3)-1;ezplot(f)xyx2/3+y2/3-1 = 0-6 -4
3、 -2 0 2 4 6-6-4-202467.螺旋线 .,sin,coctzbytax解:t=0:0.1:2*pi;x=cos(t);y=2*sin(t);z=3*t;plot3(x,y,z)-1-0.500.51-2-1012051015208.阿基米德螺线 .ar解: thear=0:0.1:2*pi; rhol=(thear); polar(thear,rhol);2468302106024090270120300150330180 09.对数螺线 .aer解: theta=0:0.1:2*pi; rhol=exp(thear); polar(thear,rhol);1002003004
4、00500302106024090270120300150330180 010.双纽线 ( ).2cos2ar)()(222yxayx解: syms x yf=(x2+y2)2-x2+y2;ezplot(f)xy(x2+y2)2-x2+y2 = 0-6 -4 -2 0 2 4 6-6-4-2024611.双纽线 ( ).sin2aryax22)(解: syms x y f=(x2+y2)2-2*x*y; ezplot(f)-6 -4 -2 0 2 4 6-6-4-20246xy(x2+y2)2-2 x y = 012.心形线 .)cos1(ar解: cleartheta=0:0.1:2*pi;r=1+cos(theta);polar(theta,r);0.511.52302106024090270120300150330180 0