Question

for an ap if tn= 4 ,d= -4 then find a​

Answer 1

Question :-

For an AP, if tₙ = 4 ,d = -4 then find a​

Answer :-

  a = 4n

Given :-

• tₙ = 4
• d = -4

To find :-

a = ?

Solution :-

  In an AP,

nth term is given by,

    $\boxed{\bf t_n=a+(n-1)d}$

where

a - first term

d - common difference

tₙ - nth term

Substitute the given values,

       tₙ = a + (n-1)d

     

      4 = a + (n - 1)(-4)

     4 = a - 4n + 4

     4 - 4 = a - 4n

      0 = a - 4n

       a = 4n

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$\underline{\underline{\textbf{Arithmetic Progression :}}}$

     Arithmetic Progression is the sequence of numbers in order in which the difference of any two consecutive numbers is a constant value.

   General form of AP,

  a, a + d, a + 2d, a + 3d,.........

Sum of n terms in Arithmetic Progression :

 $S=\frac{n}{2} [2a+(n-1)d] \\\\ S=\frac{n}{2} [a+l]$

l - last term

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