Given curve is, x2+y22x−3=0 ...(1)
Differentiating w.r.t. x d(x2+y2−2x−3)dx0
⇒2x+2y×dydx−2=0
⇒2y×dydx=2−2x
⇒dydx=2−2x2y
⇒dydx=1−xy ...(2)
Tangents are parallel to the x-axis, then the slope =0
dydx=0
⇒1−xy=0
⇒x=1
Putting x=1 in equation (1)
(1)2+y2−2(1)−3=0
⇒1+y2−2−3=0
⇒y2−4=0
⇒y2=4
⇒y=±2
Hence, the required points are (1,2) & (1,−2).