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What are the next two terms in the sequence 1,-3,6,-10,15,-21,

User Deadfish
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1 Answer

3 votes

Answer:

28, - 36

Explanation:

We are given a sequence of 1, - 3, 6, - 10, 15, -21, ..........

Now, the difference of 2nd and 1st term is (- 3 - 1) = - 4 = - 2²

Again, the difference of 3rd and 2nd term is [6 - ( -3)] = 9 =

Now, the difference of 4th and 3rd term is [- 10 - 6] = - 16 = - 4²

Again, the difference of 5th and 4th term is [15 - ( -10)] = 25 =

Now, the difference of 6th and 5th terms is [- 21 - 15] = - 36 = - 6²

Therefore, the difference of the terms are - 2², 3², - 4², 5², - 6², ..........

From this sequence, it is clear that the next two differences will be 7² i.e 49 and - 8² i.e. -64

Therefore, the next two terms of the original sequence will be (- 21 +49) = 28 and (28 - 64) = -36. (Answer)

User SeReGa
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