It is known that the left and right vertices of the ellipse e: x2 / 4 + y2 = 1 are a and B respectively. There is a moving point P on the circle x2 + y2 = 4, P is above the x-axis, C (1,0), and the line PA intersects the ellipse e at point D Connect DC and Pb. Let Pb be a straight line. The slopes of DC exist and are K1 and K2 respectively. If K1 = λ K2, calculate the value range of λ

It is known that the left and right vertices of the ellipse e: x2 / 4 + y2 = 1 are a and B respectively. There is a moving point P on the circle x2 + y2 = 4, P is above the x-axis, C (1,0), and the line PA intersects the ellipse e at point D Connect DC and Pb. Let Pb be a straight line. The slopes of DC exist and are K1 and K2 respectively. If K1 = λ K2, calculate the value range of λ

Let a (- 2,0), B (2,0), C (1,0) let P (2cos α, 2Sin α) (0 ＜ α ＜ π), D (,) then K1 = sin α / (COS α - 1) from K1 = λ K2, the equation of the line PA of λ = K1 / K2 is y = sin α * (x + 2) / (COS α + 1), and D is the intersection of the line PA and the ellipse E

If the two focuses of an ellipse and one end point of its minor axis form an equilateral triangle, then the eccentricity of the ellipse is ()
A. 12B. 32C. 34D. 64

The two focuses of the ellipse and one end point of the minor axis form an equilateral triangle, so a is chosen