绘制拟合曲线: X=0:01:1;ya=(x^2-3*x+5)*exp(-5*x)sin(x); >>yl-polyval(p3, x); plot(x,y l, x, ya, 0, y0, o) 0.15 006 00.10.20.3040.50.60.70.80.9• 绘制拟合曲线： >> x=0:.01:1; ya=(x.^2-3*x+5).*exp(-5*x).*sin(x); >> y1=polyval(p3,x); plot(x,y1,x,ya,x0,y0,'o')