I don’t understand this graph. It doesn’t seem to be on the whole numbers. What intervals is it increasing on, decreasing, or constant? How do I figure out and write the domain and range?
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Check the picture below.
yes, it doesn't have all whole numbers, is a so-called piece-wise function, whose behaviour can radically change per interval, notice the arrowheads, meaning the function continues indefinitely all the way up to ∞.