The **square root of 5** is the positive real number that, when multiplied by itself, gives the prime number 5. It is more precisely called the **principal square root of 5**, to distinguish it from the negative number with the same property. This number appears in the fractional expression for the golden ratio. It can be denoted in surd form as:

It is an irrational algebraic number. The first sixty significant digits of its decimal expansion are:

- 2.23606 79774 99789 69640 91736 68731 27623 54406 18359 61152 57242 7089... (sequence A002163 in OEIS).

which can be rounded down to 2.236 to within 99.99% accuracy. As of April 1994, its numerical value in decimal had been computed to at least one million digits.

Read more about Square Root Of 5: Proof of Irrationality, Continued Fraction, Babylonian Method, Relation To The Golden Ratio and Fibonacci Numbers, Geometry, Trigonometry, Diophantine Approximations, Algebra, Identities of Ramanujan, See Also

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**Square Root Of 5**- See Also

... Golden ratio Square root Square root of 2 Square root of 3. ...

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