Code: InterpolatingPolynomial[{{-1, 4}, {0, 2}, {1, 6}, {2,8}, {100,50}}, x]

😃 Answer

Plus[4, Times[Plus[1, x], Plus[-2, Times[Plus[3, Times[Plus[-1.33333, Times[0.0132988, Plus[-2, x]]], Plus[-1, x]]], x]]]]