Parabola, tangebt line and Normal Line intersect

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SUMMARY

The normal line to the parabola defined by the equation y = x - x² at the point (1, 0) intersects the parabola a second time. The slope of the tangent line at this point is -1, leading to the equation of the normal line being y = x - 1. To find the second intersection point, one must set the normal line equation equal to the parabola equation and solve for x, confirming the symmetry of the parabola about its axis guarantees a second intersection.

PREREQUISITES
  • Understanding of calculus, specifically derivatives and slopes of tangent lines
  • Familiarity with the properties of parabolas and their equations
  • Ability to solve quadratic equations
  • Knowledge of coordinate geometry for sketching graphs
NEXT STEPS
  • Learn how to derive equations of normal lines for various curves
  • Study the properties of parabolas, including symmetry and intersection points
  • Practice solving quadratic equations to find points of intersection
  • Explore graphical methods for visualizing intersections of lines and curves
USEFUL FOR

Students studying calculus, particularly those focusing on derivatives and geometric interpretations, as well as educators looking for examples of normal lines and parabolas in mathematical discussions.

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Homework Statement



Where does the normal line to the parabola y= x - x^2 at the point (1,0) intersect the parabola a second time? Illustrate with a sketch

Homework Equations



y= x - x^2

The Attempt at a Solution



y' = 1-2x

slope of tangent = -1 (after substituting value of x in above eq)

-ve reciprocal of (-1) = 1

equation of normal line is

y - 0 = 1 (x -1)

y = x -1

After this I am not sure how to find the second point of intersection.

I understand there has to be one since parabola is symmetric about its axis.

Thank you.
 
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You've done everything correct so far. You now have a separate equation and you want to find where it intersects the parabola. By setting the equations equal, you will get your point of intersection.
 
Thank you
 

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