Function Help! Please help me!? Thank you.?

Question

I am taking an advanced math class this year and its the second day of school and I already have homework up the wall.
Any help will be greatful

Anyway here it is:
Directions: The symbol [x] means the greatest integer not greater than x. If f(x) = [x] + 4, find each value.

1) f(-4)
2)f(-6.3)
3)f(-√3)
4) f(-4 + t)

The next question is:
Directions: Name all values of x that are not in the domain of the given function.

5) f(x) = √x^2 - 9

Thank you for your help and if you could explain it that would be great.

Thanks again!

Answer 1

Just follow the instructions.
1) since [-4] = -4, f(-4) = -4 + 4 = 0
2) since [-6.3] = -7, f(-6.3) = -7 + 4 = -3
3) since [-√3] = -2, f(-√3) = -2 + 4 = 2
4) f(-4 + t) = [-4 + t] + 4 = [t], since we do not know t
5) follow the instructions, and you can do them.