Taylor's series Flashcards
Application of Taylor’s series
To get approximation
Taylor’s series
Linear approximation
Degree = 1
f(x) = f(a) + (x-a) f’(a)
Second degree approximation
In Taylor’s series, coefficient of (x-a)ⁿ
The McLaurin series
The McLaurin series is a special case of the Taylor series where the expansion is done around x = 0
Standard expansion 1
eˣ
Standard expansion 2
sinx
Standard expansion 3
cos x
Standard expansion 4
log(1+x)
Standard expansion 5
log(1-x)
Standard expansion 6
log(1+x / 1-x)
Power series
Shortcut for nth-Degree Approximation of a Polynomial Function at x=0
Drop all terms with powers higher than n
Ex: 2nd degree approximation x³-3x²-5 at x=0 is -3x²-5
How do you handle the indeterminate form 0/0 when expanding a function around a point using Taylor series?
To expand a function f(x) around a point where it leads to an indeterminate form like 0/0
* Substitute: Set x−c=y, where c is the point of expansion
* Rewrite the function in terms of and solve it
For ex:
f(x) = sin x / x-π at x= π
Here it is of the form 0/0 at x = π
let y = x-π
function will become f(y) = sin (π+y) / y