Write the direction cosines of the vector

Write the value of

For what value of ‘a’ the vectors and are collinear?

Write the intercept cut off by the plane
2x + y – z =5 on x–axis.

Consider the binary operation* on the set {1, 2, 3, 4, 5} defined by a * b = min. {a, b}. Write theoperation table of the operation *.