<P> √ 2 appears in Viète's formula for π: </P> <Dl> <Dd> 2 m 2 − 2 + 2 + ⋯ + 2 → π as m → ∞ (\ displaystyle 2 ^ (m) (\ sqrt (2 - (\ sqrt (2 + (\ sqrt (2 + \ cdots + (\ sqrt (2)))))))) \ to \ pi (\ text (as)) m \ to \ infty) </Dd> </Dl> <Dd> 2 m 2 − 2 + 2 + ⋯ + 2 → π as m → ∞ (\ displaystyle 2 ^ (m) (\ sqrt (2 - (\ sqrt (2 + (\ sqrt (2 + \ cdots + (\ sqrt (2)))))))) \ to \ pi (\ text (as)) m \ to \ infty) </Dd> <P> for m square roots and only one minus sign . </P>

Is the square root of 200 a rational number