document.write( "Question 863222: Hi i'm not to sure if this is in the right section but hope so. I'm currently having problems with the following question.\r
\n" ); document.write( "\n" ); document.write( "Given a parametric curve x = 2sint, y=sin(2t) where t takes all values in R (real numbers)
\n" ); document.write( "(a) Find an implicit equation of this curve by eliminating t,
\n" ); document.write( "(b) Sketch this parametric curve in the xy-plane.\r
\n" ); document.write( "\n" ); document.write( "I'm more confused about a , I don't expect anyone to do (b) perhaps just inform me if my thoughts are correct.
\n" ); document.write( "Do i set it so that 0 = arcsin(x/2) - (arcsin(y))/2 --> from setting t=t OR somewhere along the lines of x + y = 2sint + sin(2t) and it's somehow a circle.. Or am I just completely off.. Thanks to anyone who responds !!
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Algebra.Com's Answer #520281 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
x = 2sin(t)
\n" ); document.write( "y = sin(2t)\r
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\n" ); document.write( "\n" ); document.write( "as far as i can tell, you eliminate t by solving for t in one of the equations and then using that value of t in the other equation.\r
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\n" ); document.write( "\n" ); document.write( "your 2 equations are:\r
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\n" ); document.write( "\n" ); document.write( "x = 2sin(t)
\n" ); document.write( "y = sin(2t)\r
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\n" ); document.write( "\n" ); document.write( "you solve for t in the first equation.
\n" ); document.write( "start with:
\n" ); document.write( "x = 2sin(t)
\n" ); document.write( "divide both sides by 2 to get:
\n" ); document.write( "x/2 = sin(t)
\n" ); document.write( "this is true if and only if arcsin(x/2) = t
\n" ); document.write( "replace t with arcsin(x/2) in the second equation to get:
\n" ); document.write( "y = sin(2*arcsin(x/2))
\n" ); document.write( "your equations are now in terms of x and f(x).
\n" ); document.write( "the equation you can graph is y = sin(2*arcsin(x/2))
\n" ); document.write( "finding the domain of this equation can be a challenge.
\n" ); document.write( "since the sine of an angle is between -1 and 1, this means that the arcsine of a number is only valid when the number is between -1 and 1.
\n" ); document.write( "since the number is x/2, this means that x has to be between -2 and 2 only.
\n" ); document.write( "in order for x to be between -2 and 2 only, this means that t has to be between -pi/2 and pi/2 only.
\n" ); document.write( "the graph of your equation is shown below:
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\n" ); document.write( "the same graph with associated data table created in Excel is shown below:
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\n" ); document.write( "\n" ); document.write( "a decent reference on parametric equations is shown below:
\n" ); document.write( "http://tutorial.math.lamar.edu/Classes/CalcII/ParametricEqn.aspx\r
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