Question

1
Sum up to n terms the series 1 + 1 +
+ 1
+
+
2
4​

Answer 1

Answer:

please write it properly

Answer 2

Answer:

sn=n/2(2a+(n-1)d

4/2(2×1+(4-1)2

2(2+3×2)

2(5×2)

2(10)

20