Deriving the Coefficients of an Infinite Power Series

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DanAbnormal
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Homework Statement



Show that if a function f(x) can be expressed as an infinite power series, then it has the form

f(x) = f(x0) + [tex]\sum^{\infty}_{n = 1}[/tex][tex]\frac{f^{n}(x0)}{n!}[/tex][tex](x - x0)^{}[/tex]

Homework Equations





The Attempt at a Solution



I know that for an infinite power series:

= f(a) + [tex]\frac{f'(a)}{1!}[/tex](x - a) + [tex]\frac{f''(a)}{2!}[/tex][tex](x - a)^{2}[/tex]...

which can be simplified into the above expression. But is there any groundwork that the question asks to get to this point here? I am thinking for 6 marsk i can't just right down the two lines...
 
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A power series has the form [itex] f(x)= \sum^{\infty}_{n = 0}<br /> a_n (x-a)^n[/itex]. You want to show [itex]f_n(a)/n!=a_n[/itex]. Differentiate the power series n times and put x=a.