Question

Graph f(x) = 2[[x]]
I know this is greatest integer function but I don't really understand where to begin solving this? Any help is appreciated!

Answer 1

The greatest integer function for any x is the nearest INTEGER to the left of it on the number line. Examples:
x = 2.3, [x] = 2
x = 0.731 , [x] = 0
x = -5.839, [x] = -6

Answer 2

Therefore, for any x, say in the interval \(2 \le x \lt 3\), [x] = 2
For any x, in the interval \(-13 \le x \lt -12\), [x] = -13

So you can plot f(x) = 2[x] for any x.

Answer 3

@aum isn't it we need to multiply any value of [x] by 2 to get f(x)?

Answer 4

Yes. But if the basics of plotting f(x) = [x] is understood first then plotting f(x) = 2[x] is very easy.

Answer 5

yup... got your point... :-)

Answer 6

http://www.wolframalpha.com/input/?i=plot+2+*+floor%28x%29

Answer 7

Wow thank you, I think I understand this much better now!