First term `a=1`, Common difference `d=2`, Number of terms `n=10`
Find `n^(th)` term (last term) and sum of the arithmetic progression
Solution:
Here first term `a=1,`
Common difference `d=2`
We know that,
`f(n) = a + (n - 1)d`
`f(10)=1 + (10 - 1)(2)`
`=1 + (18)`
`=19`
We know that,
`S_n = n/2 [2a + (n - 1)d]`
`:. S_10 = 10/2 * [2(1) + (10 - 1)(2)]`
`= 5 * [2 + (18)]`
`= 5 * [20]`
`= 100`
Hence, `10^(th)` term of the given series is `19` and sum of first `10^(th)` term is `100`
This material is intended as a summary. Use your textbook for detail explanation.
Any bug, improvement, feedback then
