Question
Write an A.P. whose first term is a and common difference is d in each of the following.
$a = – 19, d = – 4$
$a = – 19, d = – 4$
✓
Answer
$a = – 19, d = – 4$
Let $a_1 = a = – 19$
Since, the common difference d = – 4
Using formula $a_{n + 1} = a_n + d$
Thus, $a_2 = a_1 + d = – 19 + ( – 4) = – 19 – 4 = – 23$
$a_{3 =} a_2 + d = – 23 + ( – 4) = – 23 – 4 = – 27$
$a_4 = a_3 + d = – 27 + ( – 4) = – 27 – 4 = – 31$
Hence, An A.P with common difference $– 4$ is $– 19, – 23, – 27, – 31,….$
Let $a_1 = a = – 19$
Since, the common difference d = – 4
Using formula $a_{n + 1} = a_n + d$
Thus, $a_2 = a_1 + d = – 19 + ( – 4) = – 19 – 4 = – 23$
$a_{3 =} a_2 + d = – 23 + ( – 4) = – 23 – 4 = – 27$
$a_4 = a_3 + d = – 27 + ( – 4) = – 27 – 4 = – 31$
Hence, An A.P with common difference $– 4$ is $– 19, – 23, – 27, – 31,….$
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