8^ th term of the series 2 2 + 2 + 0 + ..... will be - Vidyadip

MCQ

$8^{th}$ term of the series $2\sqrt 2 + \sqrt 2 + 0 + .....$ will be

✓
$ - 5\sqrt 2 $
B
$5\sqrt 2 $
C
$10\sqrt 2 $
D
$ - 10\sqrt 2 $

✓

Answer

Correct option: A.

$ - 5\sqrt 2 $

a
(a) Obviously the given series $2\sqrt 2 + \sqrt 2 + 0 + .......$ is an $A.P.$

Here $a = 2\sqrt 2 ,\;d = - \sqrt 2 $.

Hence ${8^{th}}$ term of the series

$ = 2\sqrt 2 + (8 - 1)( - \sqrt 2 ) = - 5\sqrt 2 $.

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