Equation of a Plane with Three Points

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The discussion focuses on deriving the equation of a plane defined by three points: (a,0,0), (0,b,0), and (0,0,c). The normal vector to the plane is calculated as . The equation of the plane is expressed as Bc(x-a) + ac(y-b) + ab(z-c) = 3abc, although there is a correction suggested to -2bc. Additionally, it is noted that the point (a,b,c) does not lie on the plane, raising questions about the right side of the equation. The conversation emphasizes the importance of understanding vector relationships in defining the plane's equation.
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Equation of plane containing points (a,0,0) (0,b,0) (0,0,c)

Vectors
<-a,b,0> <-a,0,c>
Normal vector
<bc,ac,ab>

Plane
Bc(x-a)+ac(y-b)+ab(z-c)=
Bcx+acy+Abz=3abc
Book is showing = abc
 
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hi nameVoid! :smile:
nameVoid said:
Bc(x-a)+ac(y-b)+ab(z-c)=

nooo … bc(x-a)+ac(y-b)+ab(z-c) = -2bc :wink:
 
nameVoid said:
Equation of plane containing points (a,0,0) (0,b,0) (0,0,c)
Normal vector
<bc,ac,ab>
If the point <x, y, z> lies in the plane, what do you have to subtract to get a vector parallel to the plane?
 
nameVoid said:
Equation of plane containing points (a,0,0) (0,b,0) (0,0,c)

Vectors
<-a,b,0> <-a,0,c>
Normal vector
<bc,ac,ab>

Plane
Bc(x-a)+ac(y-b)+ab(z-c)=

(a,b,c) is not a point on the plane, but (a,0,0) is. And what should the right side =?
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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