Question -
Answer -
Given:
an = n2 –n+1
By using the values n= 1, 2, 3, 4, 5 we can find the first five terms.
When n = 1:
a1 =(1)2 – 1 + 1
= 1 – 1 + 1
= 1
When n = 2:
a2 =(2)2 – 2 + 1
= 4 – 2 + 1
= 3
When n = 3:
a3 =(3)2 – 3 + 1
= 9 – 3 + 1
= 7
When n = 4:
a4 =(4)2 – 4 + 1
= 16 – 4 + 1
= 13
When n = 5:
a5 =(5)2 – 5 + 1
= 25 – 5 + 1
= 21
∴ First five termsof the sequence are 1, 3, 7, 13, 21.