Finding Coordinates of Point P in Quadrant 2 with sin(-)=m

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To find the coordinates of point P in quadrant 2 where sin(-) = m, one must understand the properties of the unit circle. In this context, sin(theta) represents the y-coordinate, while cos(theta) represents the x-coordinate, with the radius of the unit circle being 1. For point P, the coordinates can be expressed as (x, y) = (cos(theta), sin(theta)), where y = m. Since P is in quadrant 2, the x-coordinate will be negative, leading to the coordinates of P being (-√(1 - m²), m). This illustrates the relationship between sine and cosine in determining the coordinates of points on the unit circle.
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Homework Statement


Point P is the intersection of the terminal arm of angle (-) in standard position and the unit circle with centre (0, 0). If P is in quadrant 2 and sin (-)= m, determine the coordinates of P in terms of m.


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The Attempt at a Solution


no idea
 
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This is a lovely example of the special properties of the unit circle. The first thing you should do though with a problem like this is draw a picture.

http://img24.imageshack.us/my.php?image=tempw.jpg
 


FalconF1, what is the definition of sin \theta and cos \theta in a unit circle?


01
 


The definition of sin theta in any case is opposite/hypotenuse and cos theta is adjecent/hypotenuse. The unit circle has a radius of 1 so any right triangle with vertices at the origin, a point P on the circle, and the X or Y axis ( is a purely your choice, most choose the X axis ) will have a hypotenuse of 1. So if you chose to drop to the X axis then sin theta = Y/1 and cos theta = X/1.
 


My teacher used to say that the easiest way to remember sin theta is Y sin
 
Last edited:
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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