What is a Taylor series?
Beginner
A An infinite sum of powers of $(x-a)$ built from derivatives at $a$
B An integral transform that maps functions to polynomials
C A geometric series with ratio equal to the function value
D A finite product of derivatives evaluated at the origin
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An infinite sum of powers of $(x-a)$ built from derivatives at $a$
A Taylor series expresses a smooth function as an infinite sum of powers of $(x-a)$, where the coefficients come from the derivatives of the function evaluated at the centre $a$.
A Maclaurin series is best described as which of the following?
Beginner
A A series using only even powers of $x$
B A Taylor series that always diverges
C The Taylor series with centre $a=0$
D A separate concept unrelated to Taylor series
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The Taylor series with centre $a=0$
Maclaurin is not a separate idea — it is the special case of the Taylor series where the centre is $a=0$.
In the general Taylor form, what does the symbol $a$ represent?
Beginner
A The highest power kept in the series
B The centre or expansion point of the series
C The remainder term of the approximation
D The radius of convergence of the series
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The centre or expansion point of the series
The point $a$ is the centre or expansion point; all derivatives are evaluated at $a$, and the series is most accurate near $x=a$.
Why does the factorial $n!$ appear in the denominator of each Taylor term?
Beginner
A It converts the series into a geometric series
B Differentiating $(x-a)^n$ repeatedly produces $n!$, which must be cancelled
C It ensures the series always converges for all $x$
D It is a convention with no mathematical reason
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Differentiating $(x-a)^n$ repeatedly produces $n!$, which must be cancelled
Repeated differentiation of $(x-a)^n$ leaves $n!$ as a constant factor. Dividing by $n!$ cancels it so the $n$-th derivative of the series matches $f^{(n)}(a)$ exactly.