Questions: Find the first five terms of the sequence a n=4 n+5. A. 5,9,13,17,21 B. 9,13,17,21,25 C. 4,8,12,16,20 D. 9,14,19,24,29

Solution Steps

The sequence is defined by the formula \( a_n = 4n + 5 \), where \( n \) is the term number. To find the first five terms, we substitute \( n = 1, 2, 3, 4, 5 \) into the formula.

1. For \( n = 1 \): \[ a_1 = 4(1) + 5 = 4 + 5 = 9 \]
2. For \( n = 2 \): \[ a_2 = 4(2) + 5 = 8 + 5 = 13 \]
3. For \( n = 3 \): \[ a_3 = 4(3) + 5 = 12 + 5 = 17 \]
4. For \( n = 4 \): \[ a_4 = 4(4) + 5 = 16 + 5 = 21 \]
5. For \( n = 5 \): \[ a_5 = 4(5) + 5 = 20 + 5 = 25 \]

The first five terms of the sequence are \( \{9, 13, 17, 21, 25\} \). This matches option B.

Final Answer