D: 5Y? +2√3Y- 1=0
y=(-√3+2√2)/5,y=(-√3-2√2)/5
y 1-y2=4√2/5
Because in the ellipse X 2+4Y 2-4 = 0, A = 2, B = 1 and C = √ 3.
X=y+√3 passes through the focus f (√ 3,0) of the ellipse.
S△AOB=S△AOF+S△FOB
= 1/2 *(y 1-Y2)√3 = 1/2 * 4√2/5 *√3 = 2√6/5