Horizontal Tangent Line
Proposition (Horizontal Tangent Line) If
then the equation of the tangent line to the curve
at the point
is
and
is said to have a horizontal tangent line at
Example (Horizontal Tangent Line) For what values of
does the graph of
have a horizontal tangent?
Solution. To find the horizontal tangent lines we find where the derivative is 0. We compute,
So we need to solve
We find,
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And using the quadratic formula we have
Thus, the values of 9x0 where the tangents lines are horizontal are
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Example (Horizontal Tangent Line) Find the points on the curve
where the tangent line is horizontal.
Solution. To find the horizontal tangent lines we find where the derivative is 0. We compute,
So we need to solve
Using the quadratic formula we have
and
Thus, the values of
where the tangents lines are horizontal are
and
Horizontal Tangent Lines
Published by Library of Math -- Online math organized by subject into topics.
Written by Smith, David A.
http://www.libraryofmath.com/horizontal-tangent-lines.html


