Question

write the interval expressing all real numbers less than or equal to 0 or greater than or equal to 1 using interval notation.​

Answer 1

The requited interval is:

• (-∞, 0] U [0, ∞)

Explanation:

We have to write two intervals in our case:

The first interval must highlight all real numbers less than or equal to 0.

Therefore,

This interval starts at -∞ and ends at 0, which is written as: (-∞, 0]

The second interval must highlight all real numbers greater than or equal to 0.

Therefore,

This interval starts at 0 and ends at ∞, which is written as: [0, ∞)

But, we have to combine these two sets. We can achieve this by placing the union symbol 'U' between the two intervals.

Therefore, the requited interval is:

• (-∞, 0] U [0, ∞)