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  1. \(f(1) = 4\text{,}\) since \(4\) is the number below 1 in the two-line notation.

  2. Such an \(n\) is \(n= 2\text{,}\) since \(f(2) = 1\text{.}\) Note that 2 is above a 1 in the notation.

  3. \(n = 4\) has this property. We say that 4 is a fixed point of \(f\text{.}\) Not all functions have such a point.

  4. Such an element is 2 (in fact, that is the only element in the codomain that is not in the range). In other words, 2 is not the image of any element under \(f\text{;}\) nothing is sent to 2.

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