Number sequences and arithmetic progression
Answers are for parents and teachers.
1
Write the first four terms of a_n = n² + 2.
3, 6, 11, 18
2
If a₁ = 3 and a_(n+1) = 2a_n − 1, find a₂, a₃, a₄.
5, 9, 17
3
Find the term a₁₀ of the progression 5, 9, 13, ...
41
4
In an arithmetic progression a₄ = 14 and a₉ = 39. Find d and a₁.
d = 5, a₁ = −1
5
Prove that a_n = 4 − 3n is an arithmetic progression and find d.
a_(n+1) − a_n = (4 − 3(n + 1)) − (4 − 3n) = −3, so d = −3.