Question 722988
Use the trigonometric substitution to write the algebraic equation as a trigonometric equation of &#952;, where &#8722;&#960;/2 < &#952; < &#960;/2. 
(4 = sqrt (64 &#8722; x^2)) , x = 8 sin &#952; 
16 = 64-x^2
x^2 = 32
x = 4sqrt(2) or x = -4sqrt(2)
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Substitute for "x":
8sin(theta) = 4sqrt(2) or 8sin(theta) = -4sqrt(2)
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sin(theta) = sqrt(2)/2; and cos(theta) = sqrt(2/2) in QI
or sin(theta) = -sqrt(2)/2 and cos(theta) = sqrt(2)/2) in QIV
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Find sin &#952; and cos &#952;. 
sin &#952;= ?
cos &#952;=?

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Cheers,
Stan H.