SOLUTION: How do you write the equation sin(2theta)=tan(theta) in rectangular form?

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Question 441746: How do you write the equation sin(2theta)=tan(theta) in rectangular form?
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
How do you write the equation sin(2theta)=tan(theta) in rectangular form
..
let theta=x
x=rcosx
y=rsinx
r^2=x^2+y^2
..
sin2x=tanx
2sinxcosx=sinx/cosx
2sinxcos^2x=sinx
multiply both sides by r^3
2rsinx*r^2cos^2x=r^3sinx
2yx^2=(x^2+y^2)y
2x^2=x^2+y^2
y^2=x^2
y^2-x^2=0
(y+x)(y-x)=0
y=-x
or
y=x