Question 3 of 44beginner💡 UnderstandShort Answer4 marks
For the following APs, write the first term and the common difference:
(i)
3, 1, -1, -3, ...
Answer
First term (a) = 3, Common difference (d) = -2
(ii)
-5, -1, 3, 7, ...
Answer
First term (a) = -5, Common difference (d) = 4
(iii)
1/3, 5/3, 9/3, 13/3, ...
Answer
First term (a) = 1/3, Common difference (d) = 4/3
(iv)
0.6, 1.7, 2.8, 3.9, ...
Answer
First term (a) = 0.6, Common difference (d) = 1.1
Explanation
This question tests the understanding of basic AP terminology. The first term is simply the first number in the sequence. The common difference is found by subtracting the first term from the second term (a₂ - a₁). The textbook explicitly states: 'we should subtract the kth term from the (k+1)th term' to find d.