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Any angle trigonometry function example 4

Question:

P is a point on the terminal side of the angle a. P has the coordinate (-1, y). sin a = square root of 3 divide by 3. Find the value of y.

In the process to solve this problem, we use the definition of sin a. sin a is equal to y divide by r, and r square is equal to x square plus y square. In which x and y are any point on the terminal side of the angle a. Because the x-coordinate of the point P is negative one, so the point P either lies in quadrant two or quadrant three. Because the value of the sin a is positive, so, the terminal side of the angle a should be either in quadrant one or in quadrant two. Therefore, the terminal side of the angle a lies in quadrant two. So, the value of y should be positive. Watch the video for the very detailed solution.