What Are the Possible Values of v2 Dot v3 and Angles Between Them in R^n?

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SUMMARY

The discussion focuses on the possible values of the dot product v2 dot v3 and the angles between the unit vectors v2 and v3 in R^n, given that v1 dot v2 = v1 dot v3 = 1/2. Using the Cauchy-Schwarz inequality, it is established that the angle between v2 and v3 in R^2 ranges from π/3 to 5π/3. The discussion also suggests that in R^3, the relationship can be visualized as a cone around the vector v1, indicating a more complex geometric interpretation.

PREREQUISITES
  • Understanding of vector dot products and their geometric interpretations.
  • Familiarity with the Cauchy-Schwarz inequality in linear algebra.
  • Knowledge of unit vectors and their properties in R^n.
  • Basic trigonometry, specifically relating angles to cosine values.
NEXT STEPS
  • Explore the geometric interpretation of dot products in R^3.
  • Study the implications of the Cauchy-Schwarz inequality in higher dimensions.
  • Learn about the properties of angles between vectors in R^n.
  • Investigate the concept of cones in vector spaces and their applications.
USEFUL FOR

Mathematicians, physics students, and anyone studying vector calculus or linear algebra who seeks to understand the relationships between vectors in multi-dimensional spaces.

Punkyc7
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Three unit vectors v1 v2 and v3 are in R^n. We are told that v1 dot v2= v1 dot v3=1/2. What are the possible values of v2 dot v3. What could the angle be between the vectors v2 and v3 give example for the cases in R^2 and R^3.

costheta = (x dot y)/((magnitude of x)(magnitude of y)


I tried using the cauchy schwarts inequality and i got the angle to be between pi/3 and 5pi/3 in R^2. I am not sure how to do R^3 or how to find the values for v2 dot v3? I am assuming that v2 dot v3 must be less then 1
 
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u know v1 dot v2 = |v1||v2|cos(t), same with v3

In R2, there should only be discrete values for t, how many?

In R3 consider a cone around the vector v1
 

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