Taylor series for 1/(1-x²)^(1/2) centered at 1

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nameVoid
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f(x)=1/(1-x^2)^(1/2)
1/x^(1/2)=1+ sum(( (-1)^n 1*3*5*7...(2n-1)(x-1)^n )/(2^n n! ) , n=1, infty )
thus 1/(1-x^2)^(1/2) = 1+ sum(( 1*3*5*7...(2n-1)(x^2)^n )/(2^n n! ) , n=1, infty )
is this a correct taylor series representation centered at 1
 
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nameVoid said:
f(x)=1/(1-x^2)^(1/2)
1/x^(1/2)=1+ sum(( (-1)^n 1*3*5*7...(2n-1)(x-1)^n )/(2^n n! ) , n, infty )
thus 1/(1-x^2)^(1/2) = 1+ sum(( 1*3*5*7...(2n-1)(x^2)^n )/(2^n n! ) , n, infty )
is this a correct taylor series representation centered at 1

Are you sure its supposed to be centered at 1? And you are sure its 1/sqrt(1-x^2)? The answer you seek is in the imaginary domain.
 
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nameVoid said:
well you for a=1 on D -1<x<1

So if f(x) = 1/sqrt(1-x^2)

What is f(1) ?
 


Mark44 said:
So it can't be centered at 1, a number not in the domain.

Would make sense that it is centered at 0 then :biggrin:
 


No, but it is probably easier. Another approach is using the definition of the Maclaurin series (since you are expanding in powers of x): f(x) = f(0) + f'(0)x + f''(0)x^2/2! + ...