Question

Find the sum of first 24 terms of the list of numbers whose n th term is given by
an=3+2n

Answer 1

Answer:

Step-by-step explanation:

N=1,2,3.....

A1=3+2+1=5

A2=3+2+2=7

A3=3+2+3=9

S24=24/2(2x5+(24-1)2)

=12(10+23x2)

=12(10+46)

=12x56

S24=672

So the answer is 672

I hope this will helps you

Answer 2

Answer:

Step-by-step explanation:

nth term:2n+3 , so 1st term = (2*1)+3 =5. so a=5.......so, first term is 5

similarly, a2=(2*2)+3, a2=7. so, a2-a=d=2.......so, common difference is 2

Sn=n/2*{2a+(n-1)d}.......so, S24=24/2[(2*5)+(24-1)2]

s24=12[10+(23)2].....s24=12[10+46].......S24=12*56.......S24=672

So, the sum of first 24 terms of the list of numbers whose n th term is given by  an=3+2n =672