If am denotes the mth term of an A.P. then am = | MATH - ARITHMETIC PROGRESSION | SolveeIt

If a_m denotes the m^th term of an A.P. then a_m =

$\frac { 2 } { a _ { m + k } + a _ { m - k } }$

$\frac { a _ { m + k } - a _ { m - k } } { 2 }$

$\frac { a _ { m + k } + a _ { m - k } } { 2 }$

None of these

Answer

$\frac { a _ { m + k } + a _ { m - k } } { 2 }$

Explanation

$a _ { m + k } = A + ( m + k - 1 ) D$ and $a _ { m - k } = A + ( m - k - 1 ) D$

Adding both equations, we get

$\frac { a _ { m + k } + a _ { m - k } } { 2 } = A + ( m - 1 ) D = a _ { m }$ .

Question: If a<sub>m</sub> denotes the m<sup>th</sup> term of an A.P. then a<sub>m</sub> =...