Assignment #1 #8 identify two crystalline directions, or vectors, in a cubic crystal which are perpendicular to the [100] vector (5 points) Note: the cosine of the angle between three arbitrary

vectors [h1, k1,11], [h2,k2,12] and [h3,k3,13] in 3D is: cos(0) = Fall 2023 h₁h₂+k₁k₂ + ₁42 (h₁² + k₁² + 1₁₂²) (h₂² + k₂² +1₂²)