<li>[SF6 1.P.035.]
A point is located in a polar coordinate system by the coordinates r = 2.0 m and = 35°. Find the x and y coordinates of this point, assuming the two coordinate systems have the same origin.</li>
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<p>For my X coordinate I got 2, which it is telling me is wrong
For my y cooridinate I got 1.12, which it is telling me is correct</p>
<p>I did:</p>
<p>x= r cos of theta = 2cos(35)= -1.80738
y= r sin of theta = 2 sin(35)= -.856368</p>
<p>r = square root of (X^2 + y^2)
r= square root of apprx. 4
so r = 2, so why is my x coordinate wrong? r IS the x coordinate. what did I do wrong.</p>
<p>Yeah, cos and sin of angles less than 90 are both positive so something is definitly wrong with that part of the calculation (presumably it is in radians). Otherwise the formula is correct.</p>
<p>x= r cos of theta = 2cos(35)= 1.64
y= r sin of theta = 2 sin(35)= 1.15</p>
<p>Note that 35 degrees implies a first quadrant angle with both sin and cos positive; </p>
<p>35 degrees is between 30 and 45 degrees, so you would expect the cosine to be between root 2 over 2 and root 3 over 2 while the sine between one half and root 2 over 2. When multiplied by r, that is 2, x should be between 1.41 and 1.71 and y should be between 1 and 1.41.</p>