Is this a correct taylor series representation 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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well you for a=1 on D -1<x<1
 


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:
 


is the binomial series only way to go here
 


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! + ...