用 Taylor幂级数展开效果将更差 > symS x; y=1/(1+25*/2); p=taylor(y, x, 10 p 1-25*x^2+625*x^4-15625*x6+390625*x^8 多项式拟合效果 >>1=-1:0.01:1; ya=1./(1+25*x1.2) 3 25 y1=subs(p, x, x1); > plot(x1, ya, -,x1,y1)s 0.5 0 180.6.40200.20.40.60.8• 用Taylor幂级数展开效果将更差。 >> syms x; y=1/(1+25*x^2); p=taylor(y,x,10) p = 1-25*x^2+625*x^4-15625*x^6+390625*x^8 • 多项式拟合效果 >> x1=-1:0.01:1; >> ya=1./(1+25*x1.^2); >> y1=subs(p,x,x1); >> plot(x1,ya,'--‘,x1,y1)