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 $D=\{2,3,5\}$
In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.
If $A \not\subset B$ and $B \not\subset C,$ then $A \not\subset C$
Write the solution set of the equation ${x^2} + x - 2 = 0$ in roster form.
Write the set $A = \{ 1,4,9,16,25, \ldots .\} $ in set-builder form.
Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:
$ 8\, .......\, A $
Let $A$ and $B$ be two non-empty subsets of a set $X$ such that $A$ is not a subset of $B$, then