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3 years ago

How do I solve this problem?

Mathematics

1 answer:

Leokris [45]3 years ago

8 0

Answer:

21, 18, 15

Step-by-step explanation:

First term = a1

Second term = a2

Third term = a3

a1 = 21

= a + d

= 21 - 3

= 18

= a + 2d

= 21 + 2 ( - 3 )

= 21 - 6

= 15

The first 3 terms are 21, 18, 15.

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Answer:

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we are given

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we can use trig identity

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