Question
The $n^{th}$ term of an AP is $(7 - 4n).$ Find its common difference.
✓
Answer
We have:
$T_n= (7 - 4n)$
Common difference $= T_2 - T_1$
$T_1= 7 - 4 \times 1 = 3$
$T_2 = 7 - 4 \times 2 = -1$
$d = -1 - 3 = -4$
Hence, the common difference is $-4$.
$T_n= (7 - 4n)$
Common difference $= T_2 - T_1$
$T_1= 7 - 4 \times 1 = 3$
$T_2 = 7 - 4 \times 2 = -1$
$d = -1 - 3 = -4$
Hence, the common difference is $-4$.
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