Find the equation of the tangent plane and normal to a surface

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SUMMARY

The discussion focuses on finding the equation of the tangent plane and the normal line to a surface defined by parametric equations. The tangent plane is derived using the partial derivatives, resulting in the equation 3x - y - 2z = 4. The normal vector is calculated as -3/2 i + 1/2 j + k, which is essential for determining the normal line equation. Participants emphasize the importance of confirming the normal line equation based on the derived normal vector and a point on the line.

PREREQUISITES
  • Understanding of parametric equations and their derivatives
  • Familiarity with vector calculus concepts, specifically cross products
  • Knowledge of the equation of a plane in three-dimensional space
  • Ability to manipulate algebraic equations for geometric interpretations
NEXT STEPS
  • Study the derivation of the normal line equation from a normal vector and a point
  • Explore examples of tangent planes in multivariable calculus
  • Learn about the geometric interpretation of partial derivatives
  • Review applications of tangent planes and normal lines in physics and engineering
USEFUL FOR

Students and professionals in mathematics, particularly those studying multivariable calculus, as well as engineers and physicists who apply these concepts in real-world scenarios.

chwala
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Homework Statement
See attached ##Q.64## highlighted in red.
Relevant Equations
vector differentiation
1714647682038.png


In my line i have,

##\dfrac{∂r}{du} = \vec{i} +\dfrac{1}{2}u \vec{k} = \vec{i} +1.5 \vec{k}##

##\dfrac{∂r}{dv} = \vec{j} -\dfrac{1}{2}v \vec{k} = \vec{j} -0.5\vec{k}##

The normal to plane is given by,

##\dfrac{∂r}{du}× \dfrac{∂r}{dv} = -\dfrac{3}{2} \vec{ i} + \dfrac{1}{2}\vec{j}+\vec{k}##

The equation of the tangent to the plane is given by,

...

##-\dfrac{3}{2} (x-3)+ \dfrac{1}{2}(y-1)+1(z-2)=0##

##-3(x-3)+(y-1)+2(z-2)=0##

##-3x+9+y-1+2z-4=0##

##-3x+y+2z+4=0##

##3x-y-2z=4##

looks good... just need to confirm/check on the Normal line equation. Insight is welcome.

Cheers.
 
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chwala said:
The equation of the tangent to the plane
Correction: The equation of the tangent plane; that is the plane that is tangent to the surface at the given point.
chwala said:
just need to confirm/check on the Normal line equation.
Did you calculate the equation of the normal line? If so you didn't include it in your work. You have a vector that has the same direction as the normal line, and a point on this line, so it's quick work to come up with the equation of that line.
 
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