Question

Interval [0, infinite symbol) this for each numerical value. Is it interval or not.

Answer 1

The given interval is

$\lbrack0,\infty)$

This interval has 0 and all positive real numbers

$x\ge0$

1) The given number is 1/25 which is a positive number then, it belongs to the given interval

$\frac{1}{25}\in\lbrack0,\infty)$

2) The given number is

$-3^3=-27$

-27 is a negative number, then it does not belong to the given interval

$-3^3\notin\lbrack0,\infty)$