flyingpig
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Two questions about rotation of this "line"
[tex]3x^2 - 2\sqrt{3}xy +y^2 = 1[/tex]
[tex]x = x'\cos\alpha - y'\sin\alpha[/tex]
[tex]y = x'\sin\alpha + y'\cos\alpha[/tex]
The discriminant test is
[tex]4(3) - 4(3)(1) = 0[/tex]
Supposed to be a parabola, instead we get lines.
One other thing
Supposed that in
[tex]cot2\alpha = \frac{A - C}{B}[/tex]
And then we get that [tex]\alpha < 0[/tex], can that happen? Can we rotate clockwise?
Homework Statement
[tex]3x^2 - 2\sqrt{3}xy +y^2 = 1[/tex]
Homework Equations
[tex]x = x'\cos\alpha - y'\sin\alpha[/tex]
[tex]y = x'\sin\alpha + y'\cos\alpha[/tex]
The Attempt at a Solution
The discriminant test is
[tex]4(3) - 4(3)(1) = 0[/tex]
Supposed to be a parabola, instead we get lines.
One other thing
Supposed that in
[tex]cot2\alpha = \frac{A - C}{B}[/tex]
And then we get that [tex]\alpha < 0[/tex], can that happen? Can we rotate clockwise?