Cubic parametric curve rotation

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I am drawing a spline based parametric curve which is described with the following functions (U for horizontal axis and Y for vertical).

$$U = A_u+B_u*p +C_u*p^2+D_u*p^3\\V = A_v+B_v*p +C_v*p^2+D_v*p^3$$ $$$$ How to rotate such a function $v(u)$ by $\theta$ degrees?

$$$$ My output equation should be composed of powers of three at max. Many thanks in advance

PS. I have seen a video How to Rotate any Curve by any Angle, but couldn't come up with a proper solution to my more complicated equation.

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A plane rotation is represented as

$$ R(\theta) = \left( \begin{array}{cc} \cos (\theta ) & -\sin (\theta ) \\ \sin (\theta ) & \cos (\theta ) \\ \end{array} \right) $$

and the rotated curve

$$ \left( \begin{array}{c} U\\ V \end{array} \right)_{\theta} = R(\theta)\left( \begin{array}{c} U\\ V \end{array} \right) $$