A
Level Maths Notes: C4 – Parametric Coordinates – Equations of
Tangents and Normals
To fins the equation of a
tangent to a curve at a point we have to find the gradient
at
that point. If
and
are
functions of
we
find
and
substitute a value for
into
this expression. If we have to find the equation of the normal to a
curve at a point
we
find
If
we have the coordinates
or
only one of these, we may have to find the value ofby
solving one or both of the equations
Example:
Find
the equation of the tangent and normal when
When
Equation of tangent:
Equation of normal:
