pell's equation
Word Rarity
Very rare
Frequency: Zipf frequency 1.70 in modern English
24
Scrabble Score
13
Letters
4
Syllables
11
Unique Chars
Meaning
noun
The Diophantine equation x²-my²=1 for a given integer m, to be solved in integers x and y.
Example Sentences
- "However, due to Euler's mistake in attributing the equation to English mathematician John Pell (1610-1585), Equation (27.14) is called Pell's equation. Results concerning Pell's equation will be stated without proof."
- "Thus (P,Q) satisfies Pell's equation and so by Lemma 1, P#47;Q is a convergent to #92;sqrtd."
- "We introduced Pell's equation #92;qquad#92;qquad#92;qquad#92;qquadx²-ny²#61;1 in Chapter 4 as an example of a Diophantine equation. The solution x#61;577,#92;y#61;408 of the Pell equation x²-2y²#61;1 was used in India in the fourth century to produce the fraction #92;tfrac#123;577#125;#123;408#125; as an excellent rational approximation for #92;sqrt 2. It is easy to see why solutions to Pell's equation can be used to approximate solutions to #92;sqrtn—this was known to Archimedes, who used this method to approximate square roots."
Etymology
Inflected Forms
Phrases
generalised Pell's equation
Pell number