Arithmetic Sequence – First Three Terms

00:00 4 marks

The first three terms of an arithmetic sequence are \(u_1\), 5, 9.
(a) Find the common difference, \(d\).
(b) Find \(u_1\).
(c) Find the value of \(u_{10}\).

Part a

2 minutes 1 marks

Question

Find the common difference, \(d\).

Hint Hint

Hint

Subtract the second term from the third term: \(d = 9 – 5\).

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Complete Answer

\(d = 4\)

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Part b

1 minutes 2 marks

Question

Find \(u_1\).

Hint Hint

Hint

Use \(u_2 = u_1 + d\) with \(u_2 = 5\) and \(d = 4\) to determine \(u_1\).

Answer Answer
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Complete Answer

\(u_1 = 1\)

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Part c

2 minutes 1 marks

Question

Find \(u_{10}\).

Hint Hint

Hint

Apply the arithmetic sequence formula \(u_n = u_1 + (n-1)d\) for \(n = 10\).

Answer Answer
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Complete Answer

\(u_{10} = 37\)

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