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Please help me! i don't know how to work this out.

the n th term is n^2+20 work out the first three terms of the sequence. how many terms in the sequence are less than 50

User Tamora
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1 Answer

3 votes

Answer:

21, 24, 29

5

Explanation:

The first term is when n = 1.

(1)² + 20 = 21

The second term is when n = 2.

(2)² + 20 = 24

The third term is when n = 3.

(3)² + 20 = 29

To find how many terms are less than 50, set n² + 20 equal to 50 and solve for n:

n² + 20 = 50

n² = 30

n ≈ 5.477

Rounding down, n = 5 is the last term that is less than 50.

Therefore, there are 5 terms in the sequence that are less than 50.

User Andrew Wilkinson
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