Question

The common difference of the A.P whose an
= -3n + 7 is
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Answer 1

$\huge\underline{\bf \orange{Solution :}}$

Given :-

$\implies \sf A_n = - 3n + 7$

Replace n by 1

$\implies \sf A_1 = - 3 \times 1 + 7 \\ \\ \implies \sf A_1 = - 3+ 7 \\ \\ \implies \sf A_1 =4$

Replace n by 2

$\implies \sf A_2 = - 3 \times2+ 7 \\ \\ \implies \sf A_2 = -6+ 7 \\ \\ \implies \sf A_2=1$

Now we have A.P

$\sf \implies4 \: ,1 \: , - 2\: , - 5$

Common difference of the A.P

$\sf \implies d = a_2 - a_1 \\ \\\sf \implies d =1 - 4 \\ \\ \implies \underline{ \boxed{ \sf d = - 3}}$

Answer 2

Hope it helps you dude

⟹d=1−4

⟹ d=−3