Equation of tangent on parabola
parabola of Class 11
Equation of tangent
yy1 = 2a(x + x1) at (x1, y1)
y = mx + 
at 
ty = x + at2 at (at2, 2at).
Note: Point of intersection of the tangents at t1 and t2 given by
x = at1t2, y = a(t1 + t2).
Normal
y − y1 = −
(x − x1) at (x1, y1)
Equation of normal in slope form at(am2, −2am) is y = mx − 2am − am3 and
y + tx = 2at + at3 at (at2, 2at).
Co-normal Points
The three points, normals at which pass through a common point are called co-normal points.
