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

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The discussion focuses on finding the equation of the tangent plane and normal line to a surface using partial derivatives. The normal to the plane is calculated as the cross product of the partial derivatives, resulting in a specific vector. The equation of the tangent plane is derived and simplified to the form 3x - y - 2z = 4. There is a request for confirmation on the normal line equation, indicating that while the direction vector is known, the actual equation has not been provided. The conversation emphasizes the need for clarity on the normal line's equation based on the derived normal vector and a point on the line.
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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