What is the range of the function

What is the principal value of ?

If then for what value of a is A an identity matrix?

What is the value of the determinant ?

Evaluate :

What is the degree of the following differential equation?

Write a vector of magnitude 15 units in the direction of vector

Write the vector equation of the following line:

If then write the value of k.

What is the cosine of the angle which the vector makes with y-axis?