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Question
Write the common difference of an A.P. whose nth term is xn + y.
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Solution
\[\text { We have }: \]
\[ a_n = xn + y\]
\[ \therefore a_1 = x + y\]
\[ a_2 = 2x + y\]
Common difference of an A.P., d = \[a_2 - a_1\]
\[\Rightarrow \left( 2x + y \right) - \left( x + y \right)\]
\[ \Rightarrow x\]
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