A curve C1 C_1\,C1 with parametric equations
x=6cost,y=25sint0≤t<2π x = 6 \cos t, \quad y = 2\sqrt{5} \sin t \quad 0 \leq t < 2\pi x=6cost,y=25sint0≤t<2πmeets the circle C2 C_2\,C2 with equation
x2+y2=25 x^2 + y^2 = 25 x2+y2=25at four distinct points as shown in the diagram.
Show that the Cartesian equation of C1 C_1\,C1 is
x236+y220=1 \frac{x^2}{36} + \frac{y^2}{20} = 1 36x2+20y2=1Find the Cartesian coordinates of the points of intersection.
215 exam-style questions on Edexcel A Level Maths Parametric Equations, covering 8.1 Parametric Equations, 8.2 Using Trigonometric Identities, 8.3 Curve Sketching, 8.4 Points of Intersection, and 8.5 Modelling with Parametric Equations. Each one has a worked solution and a mark scheme showing where the marks go.