Answer: which is Choice B
This is the same as writing
The second "2" is not under or inside the square root.
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Explanation:
Refer to the unit circle below. I've highlighted the angle 45 degrees and its corresponding sine value. It's the y coordinate of the point on the unit circle, for this particular angle.
Therefore,
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You could alternatively draw out a 45-45-90 triangle. Let x be the leg length and the hypotenuse is 1 unit long. Solve for x and you should get
as the length of each leg.
Then take the ratio of the opposite over hypotenuse to find the same answer mentioned above.
