Find the 50th term of the
following series:
1 + 3 + 7 + 13 + 21
+ ............
Solution: 2451
Explanation:
t2 – t1
= 2 (2*1)
t3 – t2
= 4 (2*2)
t4 – t3 = 6 (2*3)
………………………..
…………………………
………………………..
t50 – t49
= 98 (2*49)
Adding all the equations,
we get
t50 – t1
= 2 + 4 + 6 + ………. + 98
t50 – t1
= 2450
t50 – 1 = 2450
Therefore, t50 =
2451