# Formula:KLS:09.08:62

**Failed to parse (LaTeXML (experimental; uses MathML): Invalid response ("") from server "http://latexml:8080/convert/":): {\displaystyle {\displaystyle \frac{1-xt}{1-2xt+t^2}=\sum_{n=0}^{\infty}\ChebyT{n}@{x}t^n }}**

## Proof

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## Symbols List

**Failed to parse (LaTeXML (experimental; uses MathML): Invalid response ("") from server "http://latexml:8080/convert/":): {\displaystyle {\displaystyle \Sigma}}**
: sum : http://drmf.wmflabs.org/wiki/Definition:sum

**Failed to parse (LaTeXML (experimental; uses MathML): Invalid response ("") from server "http://latexml:8080/convert/":): {\displaystyle {\displaystyle T_{n}}}**
: Chebyshev polynomial of the first kind : http://dlmf.nist.gov/18.3#T1.t1.r8

## Bibliography

Equation in Section 9.8 of **KLS**.

## URL links

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