Advertisements
Advertisements
प्रश्न
Find the first four terms of the sequence whose nth terms are given by an = (–1)n+1 n(n + 1)
उत्तर
an = (–1)n+1 n(n + 1)
a1 = (–1)1+1 (1) (1 + 1)
= (–1)2 (1) (2) = 2
a2 = (–1)2+1 (2) (2 + 1)
= (–1)3 (2) (3)= – 6
a3 = (–1)3+1 (3) (3 + 1)
= (–1)4 (3) (4) = 12
a4 = (–1)4+1 (4) (4 + 1)
= (–1)5 (4) (5) = – 20
∴ The first four terms are 2, – 6, 12, – 20, …
APPEARS IN
संबंधित प्रश्न
Find the next three terms of the following sequence.
8, 24, 72, …
Find the next three terms of the following sequence
`1/4, 2/9, 3/16, ...`
Find the first four terms of the sequence whose nth terms are given by an = n3 – 2
Find the nth term of the following sequence
2, 5, 10, 17, ...
Find the nth term of the following sequence
`0, 1/2, 2/3, ...`
Find the nth term of the following sequence
3, 8, 13, 18, ...
Find the indicated terms of the sequences whose nth terms are given by
an = `(5"n")/("n" + 2)`; a6 and a13
Find a8 and a15 whose nth term is an = `{{:(("n"^2 - 1)/("n" + 3)";", "n is even""," "n ∈ N"),(("n"^2)/(2"n" + 1)";", "n is odd""," "n ∈ N"):}`
If a1 = 1, a2 = 1 and an = 2an−1 + an−2, n ≥ 3, n ∈ N, then find the first six terms of the sequence
The next term of the sequence `3/16, 1/8, 1/12, 1/18, ...` is