How to find out equation of a plane intersecting with other ?

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SUMMARY

The discussion focuses on determining the normal vector of a plane intersecting with another plane, given a point on the intersection line, the normal vector of one plane, and the angle between the two planes. The normal vector of the unknown plane is perpendicular to the line of intersection, leading to the equations n.v = 0 and n.m = -cos(x), where n is the unknown normal, m is the known normal, and x is the angle between the planes. The cross product of the two normals can be utilized to find the third normal vector, which is parallel to the line of intersection.

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  • Understanding of vector mathematics, specifically normal vectors
  • Familiarity with the concept of plane intersections in three-dimensional space
  • Knowledge of trigonometric relationships involving angles between vectors
  • Proficiency in performing vector operations, including cross products
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  • Study vector algebra and its applications in geometry
  • Learn about the geometric interpretation of cross products in 3D space
  • Explore the properties of angles between planes and their normals
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Mathematicians, physics students, engineers, and anyone involved in 3D modeling or computational geometry who seeks to understand the relationships between intersecting planes.

the_rising
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Hello everyone,
My question is -- Suppose we have two planes intersecting each other in some line. If we know a point on the intersecting line and the normal vector of the one plane and the angle between two planes, can we find out the normal vector of the other plane ?
Please respond.

Regards,
 
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The normal vector of the unknown plane is perpendicular to the line of intersection, so if the line is parallel to the vector v, then n.v = 0, where n is the normal of the unknown plane. If m is the normal vector of the known plane, take m/|m| to ensure you have a vector of length 1. Stipulate that |n| = 1. Then n.m = |n||m|cos(pi - x) = cos(pi - x) = -cos(x), where x is the known angle between planes. You have two important equations:

n.m = -cos(x)
n.v = 0

In fact, you also know that:

v.m = 0

Try to use these.
 
mmmmmm...just take the cross product of the 2 normals to get the 3rd normal which will will be parallel to the line of intersection. and depending on what point P0you want it to pass through
N.P-N.P0=0 --> so if n and m are the normals

(nxm).(P-P0)=0 is your solution where P is just variables
 

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