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 $A.P.$
(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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