The Z-transform of x[n] = αnu[n] is;
1
\( \frac{-z}{{z - α}},\;\left| z \right| > \left| α \right|\)
2
\( \frac{α}{{z - α}},\;\left| z \right| > \left| α \right|\)
3
\( \frac{z}{{z - α}},\;\left| z \right| > \left| α \right|\)
4
\( \frac{-α}{{z - α}},\;\left| z \right| > \left| α \right|\)
5
\( \frac{-z}{{z+ α}},\;\left| z \right| = \left| α \right|\)