Question 918196
A. Find the missing coordinate of P, using the fact that P lies on the unit circle in the given quadrant. 
Quadrant 2 
Coordinates P(−3/4,?)
 My answer (-3/4,7/4)
Correct answer:: (3/4)^2 + ?^2 = 1
(0.75 + ?^2 = 1
?^2 = 0.25
? = 0.5
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B. The point P is on the unit circle. Find P(x, y) from the given information. 
The x-coordinate of P −2/5 
P lies above the x-axis. 
My answer: P(x, y) = (-2/5,21/5)
Correct answer::
(2/5)^2 + y^2 = 1
y^2 = 1 - 4/25
y^2 = 21/25
y = sqrt(21)/5
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C. Find the terminal point P(x, y) on the unit circle determined by the given value of t. 
t = −3π/4 (in QII)
My answer: P(x, y) = (-√2/2, -√2/2)
Correct answer:: (-sqrt(2)/2, +sqrt(2)/2)
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Cheers,
Stan H.
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