Question

f(x) = [[x]], what is f(0.9)?

f(0.9) = -1
f(0.9) = 0
f(0.9) = 0.9
f(0.9) = 1
f(0.9) = -0.9

Answer 1

I believe the answer you're looking for is f(0.9) = 0.9

If you replace the first x with 0.9, you will be replacing any other x's in the problem with that value as well.

Since f(x) = x

f(0.9) = 0.9