Write the following sets in roster form :
$D = \{ x:x$ is a prime number which is divisor of $60\} $
$D = \{ x:x$ is a prime number which is divisor of $60\} $
$2$ | $60$ |
$2$ | $30$ |
$3$ | $15$ |
$5$ |
$\therefore 60=2 \times 2 \times 3 \times 5$
The elements of this set are $2,3$ and $5$ only.
Therefore, this set can be written in roster form as $D=\{2,3,5\}$
Write the following sets in the set-builder form :
$\{ 3,6,9,12\}$
Which of the following are examples of the null set
$\{ x:x$ is a natural numbers, $x\, < \,5$ and $x\, > \,7\} $
If $A = \{ 1,\,2,\,3,\,4,\,5\} ,$ then the number of proper subsets of $A$ is
List all the elements of the following sers :
$E = \{ x:x$ is a month of a year not having $ 31 $ days ${\rm{ }}\} $
Write the following as intervals :
$\{ x:x \in R, - 12\, < \,x\, < \, - 10\} $