Question

0.4 Derive the formulae to find nth term of the sequence of even and odd natural numbers
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Answer 1

Answer:

6Given: S

n

=n

2

+2n...(i)

S

n−1

=(n−1)

2

+2(n−1)=n

2

+1−2n+2n−2=n

2

−1...(ii)

Subtracting eq (ii) from (i), we get

t

n

=S

n

−S

n−1

=n

2

+2n−n

2

+1=2n+1

The n

th

term of an AP is 2n+1.