Which of the following correctly uses the explicit formula, An=1/4+(n−1)⋅1/2, to find the 9th term of the described arithmetic sequence?
To find the 9th term of the arithmetic sequence using the explicit formula An=1/4+(n−1)⋅1/2, substitute n = 9 into the formula and simplify.
A9 = 1/4 + (9-1)(1/2)
A9 = 1/4 + (8)(1/2)
A9 = 1/4 + 4
A9 = 1/4 + 16/4
A9 = (1+16)/4
A9 = 17/4
Therefore, the 9th term of the arithmetic sequence is 17/4.