`*`(A, `*`(Série, `*`(de, `*`(Taylor, `*`(da, `*`(função, `*`(f(x)))))))) = `^`(e, x) 

 

Vimos em aula que 

 

O polinômio de Taylor da `^`(e, x) de ordem n é dado abaixo 

T[n](x) = `+`(1, x, `/`(`*`(`^`(x, 2)), `*`(factorial(2))), `/`(`*`(`^`(x, 3)), `*`(factorial(3))), `/`(`*`(`^`(x, 4)), `*`(factorial(4))), ` . . . `, `/`(`*`(`^`(x, n)), `*`(factorial(n))))=Sum(`/`(`*`(`^`(x, i)), `*`(factorial(i))), i = 0 .. n). 

Os polinômios de Taylor de ordem de 1 a 5 são descritos a seguir 

 

 

 

 

 

T[0](x) = 1
T[1](x) = `+`(1, x)
T[2](x) = `+`(1, x, `*`(`/`(1, 2), `*`(`^`(x, 2))))
T[3](x) = `+`(1, x, `*`(`/`(1, 2), `*`(`^`(x, 2))), `*`(`/`(1, 6), `*`(`^`(x, 3))))
T[4](x) = `+`(1, x, `*`(`/`(1, 2), `*`(`^`(x, 2))), `*`(`/`(1, 6), `*`(`^`(x, 3))), `*`(`/`(1, 24), `*`(`^`(x, 4))))
T[5](x) = `+`(1, x, `*`(`/`(1, 2), `*`(`^`(x, 2))), `*`(`/`(1, 6), `*`(`^`(x, 3))), `*`(`/`(1, 24), `*`(`^`(x, 4))), `*`(`/`(1, 120), `*`(`^`(x, 5)))) (1)
 

Graficamente, termos 

> `assign`(i, 'i'); -1; `assign`(n, 'n'); -1; plot([exp(x), seq(sum(`/`(`*`(`^`(x, i)), `*`(factorial(i))), i = 0 .. n), n = 1 .. 5)], x = -3 .. 3, thickness = 2); 1
 

Plot_2d
 

>
 

>
 

A seguir, temos uma ilustração quando determinamos os polinômios com ordem variando de 1 a 60. 

 

> `assign`(m, 60); 1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2 ...
`assign`(m, 60); 1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2 ...
`assign`(m, 60); 1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2 ...
`assign`(m, 60); 1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2 ...
`assign`(m, 60); 1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2 ...
 

 

60
Plot_2d
 

>
 

A seguir, temos uma ilustração da convergência da série para `^`(e, x) variando a ordem de 1 a 60. 

 

> `assign`(m, 60); -1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2...
`assign`(m, 60); -1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2...
`assign`(m, 60); -1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2...
`assign`(m, 60); -1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2...
`assign`(m, 60); -1; `assign`(frms, seq(plot([exp(x), convert(taylor(exp(x), x, i), polynom)], x = -20 .. 5, y = -2 .. 10, color = [red, COLOR(HUE, `/`(`*`(i), `*`(`+`(m, 2))))], thickness = 2), i = 2...
 

Plot_2d
 

>