### Question:
Vector3D { public static float[] vectorMultiply(float[] lhs, float[] rhs) { float[] result = new float[3]; result[x] = lhs[y]*rhs[z] - lhs[z]*rhs[y]; result[y] = lhs[z]*rhs[x] - lhs[x]*rhs[z]; result[z] = lhs[x]*rhs[y] - lhs[y]*rhs[x]; return result; }  static float[] vectorMultiply(float[] lhs, float[] rhs); static float scalarMultiply(float[] lhs, float[] rhs); static float distanceVertices(float[] left, float[] right); static float vectorLength(float[] vector); static float[] createVector(float[] start, float[] end); static float distanceDotLine(float[] dot, float[] lineA, float[] lineB); static float distancevertexSegment(float[] dot, float[] segmentStart, float[] segmentEnd); static final float Epsilon; }### Answer:
@Test public void vectorMultiply() throws Exception { float vec1[] = {1, 0, 0}; float vec2[] = {0, 1, 0}; float res[] = Vector3D.vectorMultiply(vec1, vec2); assertTrue(vectorEqual(res, new float[] {0, 0, 1})); res = Vector3D.vectorMultiply(vec2, vec1); assertTrue(vectorEqual(res, new float[] {0, 0, -1})); float[] vec3 = {1, 2, 3}; float[] vec4 = {4, 5, 6}; res = Vector3D.vectorMultiply(vec3, vec4); assertTrue(vectorEqual(res, new float[] {-3, 6, -3})); res = Vector3D.vectorMultiply(vec4, vec3); assertTrue(vectorEqual(res, new float[] {3, -6, 3})); res = Vector3D.vectorMultiply(vec4, vec4); assertTrue(vectorEqual(res, new float[] {0, 0, 0})); }