BCMaclaurin series (Taylor series centered at a = 0)
f(x) = e^xP_{3}(x)
Maclaurin polynomial, degree 3
P_{3}(x) = 1 + x + \frac{x^2}{2!} + \frac{x^3}{3!}
Converges to f(x) = e^x on (-\infty, \infty).
f(0.5)
1.6487
P_3(0.5)
1.6458
error
0.0029
Every coefficient is c_k = \dfrac{f^{(k)}(0)}{k!}. That is why raising the degree adds one more term and pulls P_{3} closer to the curve.
| k | f^{(k)}(0) | k! | c_k = f^{(k)}(0)/k! |
|---|---|---|---|
| 0 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 |
| 2 | 1 | 2 | \frac{1}{2} |
| 3 | 1 | 6 | \frac{1}{6} |
| 4 | 1 | 24 | \frac{1}{24} |
Taylor Series Builder: Coefficients from Derivatives from CalcLearn, free AP Calculus study tools.