Question

What does surd refer to?

Answer 1

If you take it in math's sense then it is number thats irrational or the irrational root of an integer ............
n if you wanna take it in normal english then it is a sound, a type of sound spoken using breath and not using your sound (voice) ........

Hope it helps !!

Answer 2

Surds. When we can't simplify a number to remove a square root (or cube root etc) then it is a surd. Example: √2 (square root of 2) can't be simplified further so it is a surd. Example: √4 (square root of 4) can be simplified (to 2), so it is not a surd!

In general, an unresolved nth root, commonly involving a radical symbol , is known as a surd. However, the term surd or "surd expression" (e.g., Hardy 1967, p. 25) can also be used to mean a sum of one or more irrational roots. In the mathematical literature, the term arises most commonly in the context of quadratic surds.

The term "surd" has a special meaning in the Wolfram Language, where the principal th root of a complex number  can be found as z^(1/n) or equivalently Power[z, 1/n]. However, when  is real and only real roots are of interest, the command Surd[x, n] which returns the real-valued th root for real  odd  and the principal th root for nonnegative real  and even  can be used.