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2 years ago

Cot (15 degrees)

Mathematics

1 answer:

STatiana [176]2 years ago

8 0

Answer:

Part I: cot(15 degrees) = cot(45 - 30)

Part II: Evaluation is below

Step-by-step explanation:

<em>Everything is done in degrees</em>

<em />

Two angles that differ by 15 degrees that is easy to evaluate is 30 degrees and 45 degrees. The cot(15 degrees) = cot(45 - 30) = 1/tan(45-30) = (1+tan45tan30)/(tan30 - tan45) = (1+ sqrt(3))/(sqrt(3) - 1)

We rationalize this by multiplying 1+ sqrt(3) in the top and bottom, getting:

(4 + 2sqrt(3))/2 = 2 + sqrt(3)

I hope this helps! :)

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