# Aptitude - Square Root and Cube Root - Discussion

Discussion Forum : Square Root and Cube Root - General Questions (Q.No. 13)
13. 3 - 1 2 simplifies to: 3
 3 4
 4 3
 4 3
None of these
Explanation: 3 - 1 2 = (3)2 + 1 2 - 2 x 3 x 1 3 3 3

 = 3 + 1 - 2 3

 = 1 + 1 3

 = 4 3

Discussion:
9 comments Page 1 of 1.

Aswin said:   5 years ago
In this sum, why don't we use BODMAS condition?

Yash Badgujar said:   7 years ago
= sqrt3/1 - 1/sqrt3.
= sqrt9 - 1/sqrt3.
= (3 - 1/sqrt3)^2.
We know that,
(a/b)^2 = a^2/b^2.
so,
= (2^2)/(sqrt3^2).
= 4/sqrt9.
= 4/3.

Simi said:   7 years ago
Use the formula:

(a-b)^2 = a^2 + b^2 - 2(a*b).

Joha said:   7 years ago
Any one please explain this sum?

Joslin said:   8 years ago
Taking LCM.

= (sqrt3- 1/sqrt3)^2.
= ( (3-1)/sqrt3)^2.
= (2/sqrt3)^2.
= 4/3.

Amit said:   8 years ago
It is (a-b)square = (a square+b square-2ab).

Kalaiarasi said:   8 years ago
How to calculate LCM?

Abhilash said:   9 years ago
By doing LCM b/w root3 and 1/root3 also we can get that easily.