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Glite Dictionary
🤫 A voiceless sound 🤫 Voiceless (phonetic) √ An irrational number
surd

surd

9.9
A number that cannot be written as a simple fraction, often a square root
  • noun
  • /sɜrd/
  • UK
translation icon : número irracional
  • To solve the equation, we need to evaluate the surd that appears under the radical sign.

Examples

  • In mathematics, a surd is often represented by roots that do not resolve into whole numbers.

  • "This is a surd.

    Fiction book (1999)

  • The number sqrt(2) is considered a surd because it cannot be simplified into a fraction.

Synonyms

irrational number
vssurd
  • Specialized
1 5.6

A number that cannot be written as a fraction, for example π or √2

is more narrowly about roots that cannot be simplified

Antonyms

rational number
  • Specialized
1 3.8

A number that can be written as a fraction like 3/4 or -1/2

Surface Forms

surd singular
surd plural

Etymology

Surd in mathematics also traces back to Latin surdus meaning 'deaf' or 'silent', and a helpful way to remember this is to think of a surd as a number that cannot be 'spoken' as a simple fraction, so it is 'silent' or hard to express in that simple form.