Sums of sequences
Gemoetric sum
Arithmetic sum
Infinite sum
Σ
Σ
k=2
15
(2)(-4)*k-1
k=1
∞
Σ
k=5
50
3k+1
n
2(0.2)^k-1
n
50-5+1=46
a1
an
3(5)+1=16
3(50)+1=151
S∞=a1/1-r=2/1-0.2
Sn
n(a1+an/2)
r <1
r >1
3841=
convergent
divergent(no sum)
r
15-2+1=14
-4
a1
(2)(-4)*2-1 = -8
Sn
a1(1-r*n)/(1-r)
=-429496731.2
done by: sara alsaed-halah algadi