4 years ago

The nth term of a sequence is n^2 -n-2 .find the sum of the first and third terms

Mathematics

1 answer:

Troyanec [42]4 years ago

8 0

Answer:

Step-by-step explanation:

substitute n=1 and n=3 in the given equation

1 st term is (1)^2-1-2 = 1 -1 -2 = -2

3rd term is (3)^2-3-2 = 9-3-2=4

sum of 1st and 3rd term is -2 + 4 = 2

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Answer:

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Step-by-step explanation:

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As the interior angles in a triangle are added up to 180°

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