Question

2. Which of the following sequences is not
an AP?
(A) -3, -2, -1, 1, 2, ..........
(B) -7, -5, -3, -1, 1, ...
(C) 7, 12, 17, 22, 27, .........
(D) 6, 9, 12, 15, 18, .....
​

Answer 1

Hey there.....!!

Answer➡

(A) -3,-2,-1,1,2 is not an AP

We all know that,

For a series to be in AP the common difference must remain the same but in the above series the common difference varies.

(A) -3,-2,-1,1,2

Common difference = Succeeding - Preceding term

-2 - (-3) = 1

-1 - (-2) = 1

1- (-1) = 2

2 - 1 = 1

Here the common difference is different, hence it doesn't form an AP.

(B) -7,-5,-3,-1,1

Common difference➡

-5 -(-7) = 2

-3 - (-5) = 2

-1 - (-3) = 2

1 - (-1) = 2

Hence it forms an AP.

(C) 7,12,17,22,27

Common Difference➡

12-7 = 5

17-12 = 5

22-17 = 5

27-22 = 5

Common difference remains same and thus the series is in AP.

(D) 6,9,12,15,18

Common difference➡

9-6 = 3

12-9 = 3

15-12 = 3

18-15 = 3

Common difference remains same and thus the series is in in AP.

Hope this helps!!!

Answer 2

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HeYaA mAtE

Here is your answer:-

______________________________

▇ ▅ █ ▅ ▇ ▂ ▃ ▁ Option A▁ ▅ ▃ ▅ ▅ ▄ ▅ ▇

_______________________________

Because all other options are in a perfect sequence excluding Option A

$\huge\bold\red{option \:A}$

Their differences

-3 and -2 = 1

-2 and -1 = 1

-1 and 1 = 2

1 and 2 = 1

Hence ,

It is not in a proper sequence❎

$\huge\bold\red{option\: B}$

Difference:-

-7 and -5 = 2

-5 and -3 = 2

-3 and -1 = 2

-1 and 1 = 2

Hence ,

It is in a proper sequence✔️

$\huge\bold\red{Option \:C}$

Difference:-

7 and 12 = 5

12 and 17 = 5

17 and 22 = 5

22 and 27 = 5

Hence ,

It is in a proper sequence✔️

$\huge\bold\red{Option \:D }$

Difference:-

6 and 9 = 3

9 and 12 = 3

12 and 15 = 3

15 and 18 = 3

Hence ,

it is in proper sequence✔️
$<Marquee>$
Hope it helps you

Regards

Adi