Question

Question 6
If two positive integers a and b are written as $a=x^3{y}^{2}andb=x{y}^2$ where x, y are prime numbers, then HCF (a, b) is

A) $xy$
B) $x{y}^2$
C) $x^3{y}^3$
D) $x^2{y}^2$

Answer 1

The answer B.
Given that, $a=x^3{y}^2=x\times x\times x\times y\times y$
$b=x{y}^3=x\times y\times y\times y$
$\therefore$ HCF of a and b = HCF $(x^3{y}^2,x{y}^3)=x\times y\times y=x{y}^2$
[HCF is the product of the smallest power of each common prime facter involved in the numbers]