If the \(n\)th term of an arithmetic progression is \(a_n=4n-7\), which correctly identifies its first term and common difference?
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Answer and explanation
Correct answer: First term \(-3\) and common difference \(4\)
Putting \(n=1\) gives \(a_1=4(1)-7=-3\). The coefficient of \(n\) is 4, so each successive term increases by 4; hence the common difference is 4. Exam tip: always verify the first term using \(n=1\).
Frequently asked questions
What is the correct answer to this question?
First term \(-3\) and common difference \(4\)
Why is this the correct answer?
Putting \(n=1\) gives \(a_1=4(1)-7=-3\). The coefficient of \(n\) is 4, so each successive term increases by 4; hence the common difference is 4. Exam tip: always verify the first term using \(n=1\).
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.
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