Explore Westonci.ca, the leading Q&A site where experts provide accurate and helpful answers to all your questions. Connect with a community of experts ready to help you find solutions to your questions quickly and accurately. Join our platform to connect with experts ready to provide precise answers to your questions in different areas.

Calculate the sum of the first n terms of the arithmetic progression (an)
a) a, = -4; d = 2; n = 16
please help me


Sagot :

Answer:

n²-5n

Step-by-step explanation:

The sum of the nth term is expressed as;

Sn =n/2[2a+(n-1)d]

Given

a, = -4; d = 2; n = 16

Sn = n/2[2(-4)+(n-1)2]

Sn =n/2[-8+2n-2]

Sn = n/2[2n-10]

Hence the sum of the nth term is 2n²-10n/2

2n(n-5)/2

= n(n-5)

= n²-5n

The sum of the nth term is n²-5n