term(n) = -1.5n +c
so when n = 1 your want term(1) to be 20
-1.5(1)n + c = 20
c = 21.5
term(n) = -1.5n + 21.5 , where n is a natural number
now just put that in the notation that you must have studied.
Write the mathematical expression that describes the arithmetic sequence.
Use sigma notation to describe the sum of the first ten terms of the arithmetic sequence
20, 18.5, 17, 15.5, 14, (the difference is from -1.5)
Help, please!
1 answer
1 answer