Write the first five terms of each of the sequences in Exercises 1 to 6 whose nth terms are: an = (-1)n - 1 5n + 1.
Solution and Explanation
Substituting n = 1, 2, 3, 4, 5, we obtain
a1 = (-1)1-1 51+1 = 52 = 25
a2 = (-1)2-1 52+1 = -53 = -125
a3 = (-1)3-1 53+1 = -54 = 625
a4 = (-1)4-1 54+1 = -55 = -3125
a5 = (-1)5-1 55+1 = 56 = 15625
Therefore, the required terms are 25, –125, 625, –3125, and 15625.
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