matlab函数图像图例怎么修改（三条曲线变成不同颜色）

>> clear
clc
x=0:0.1:1;
a=3;
y=inline('a*10^(-10)','x','a');
fy = zeros(length(x),1);
for i = 1:length(x)
fy(i)=y(x(i),a);
end
plot(x,fy)
hold on;
clear
clc
x=0:1
y=1.39*10^(-10)*exp(x-x);
plot(x,y);
hold on
clear
clc
x=0:0.1:1;
a=0.1059;
b=2.5;
y=inline('1.455*10^(-12)/a/(1-x)/(log(1-x))^2','x','a','b');
fy = zeros(length(x),1);
for i = 1:length(x)
fy(i)=y(x(i),a,b);
end
plot(x,fy)
legend('正弦曲线','余弦曲线','余曲线')
title('正弦与余弦曲线')
xlabel('23')
ylabel('ewe')

要改成这种