Part 1
Find the common difference to this arithmetic sequence, then find and the equation.
1, -4, 16, -64, 256, -1024, …
= + (n-1) d
= 1 + (50-1) -4
= 1+ (-196)
= -195
Part 2
The common difference is a multiplecation of -4 when starting at 1.
= ( + )
= [1+ (-195)]
= [-194]
= 25 [-194]
= -4850