What is the sum of the first 47 terms of the sequence?

−215,−201,−187,−173,...

TheFA May 27, 2019

#1**+2 **

This is an ARITHMETIC series with common difference, d = 14 a1 = -215

a47 = a1 + (47-1)(14)

= -215 + 46(14) = 429

S_{47} = n(a1+a47)/2 = 47(-215 +429)/2 = 5029

ElectricPavlov May 28, 2019

#1**+2 **

Best Answer

This is an ARITHMETIC series with common difference, d = 14 a1 = -215

a47 = a1 + (47-1)(14)

= -215 + 46(14) = 429

S_{47} = n(a1+a47)/2 = 47(-215 +429)/2 = 5029

ElectricPavlov May 28, 2019