Which of the following rules defines the nth term of an arithmetic progression for every positive integer n?
Answer and explanation
Correct answer: \(a_n=7n-3\)
For \(a_n=7n-3\), \(a_{n+1}-a_n=[7(n+1)-3]-(7n-3)=7\), a constant difference; hence it is an AP. In \(n^2+7\), the differences vary. Exam tip: a linear expression in n represents an AP.
Frequently asked questions
What is the correct answer to this question?
\(a_n=7n-3\)
Why is this the correct answer?
For \(a_n=7n-3\), \(a_{n+1}-a_n=[7(n+1)-3]-(7n-3)=7\), a constant difference; hence it is an AP. In \(n^2+7\), the differences vary. Exam tip: a linear expression in n represents an AP.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Arithmetic Progressions (AP). Topic: Finding the $n$th term of an AP.