+0

# Which of the following is NOT a surd ?

0
634
4
+8

Which of the following is NOT a surd?

A

√9 + √7

B

√9 - √7

C

√(9 + 7)

D

√(9 - 7)

head- to- toes-smart  Jul 26, 2014

#3
+10

CPhill, that sounds absurdly irrational!

I hope you can hear this.

Guest Jul 27, 2014
#1
+4472
+10

C is not a surd.

sqrt(9+7) = sqrt(16) = 4

The rest are decimals since they cannot be simplified to remove the sqrt symbol.

sqrt(9) by itself is not a surd, but with the + / - sqrt(7) [which cannot be simplified like sqrt(4), sqrt(25), etc.] it is a surd.

AzizHusain  Jul 26, 2014
#2
+90088
+10

I've not run across the term "surd" before......Simply put, it is a number that cannot be simpified to remove a root (an irrational number is the result).....

How did we get the word "Surd" ?

Well around 820 AD al-Khwarizmi (the Persian guy who we get the name "Algorithm" from) called irrational numbers "'inaudible" ... this was later translated to the Latin surdus ("deaf" or "mute")

CPhill  Jul 27, 2014
#3
+10

CPhill, that sounds absurdly irrational!

I hope you can hear this.

Guest Jul 27, 2014
#4
+93691
+5

I can - All smiles from me.

Melody  Jul 27, 2014