1. So far, the functions we have been working with have
been explicitly expressed in terms of one variable:
y = f(x) y = sin(x) y = 3x-5
We often see relations like these:
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We can solve these for y in terms of x.
But there are some equations which we can not solve
for y:
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These relations are said to be implicitly defined and we
can find their derivatives using implicit differentiation.
2. Examples:
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3. Define orthogonal curves:
Curves which are perpendicular to each other.
Define Normal to a curve
A normal to a curve is the line perpendicular to the
tangent line at that point.
Example: