How/Why do you get the solutions to a trigonometry equation with multiple angles?

Explain why the solutions to cos(2x)=(22) of the interval [0,2π) are what they are!

1 Answer
Nov 9, 2015

For the example cos(2x)=(22), the reason the answers {π4,7π4,9π4,15π4} are in the first and fourth quadrant are because cosine is positive in those quadrants. That is what is asking for.

Explanation:

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Realized my mistake and answered my own question. I had not realized it was a cosine and wasn't thinking about the quadrants.