Question

How do you find an equation that describes the sequence `3, 8, 13, 18,...` and find the 70th term?

Answer 1

`color (green)(70^(th) "term"` `color(green)( a_70 = 348`

Explanation:

`a_1 = 3` First to find common difference `d`.

`d = a_2 - a_1 = a_3 - a_2 = a_4 - a_3 = 5`

`a_n = a_1 + (n-1) * d`

Therefore `a_70 = a_1 + (70 -1 ) * d = 3 + 69 * 5 = 348`