Question
For what value of c the vector will be perpendicular to:
(i) Z-axis (ii) Y-axis?
Solution
(i) Vector is perpendicular to Z-axis if its dot product with
is zero.
i.e.
The equation is satisfied for all values of c.
Therefore is always perpendicular to Z-axis whatever the value of c.
(ii) Similarly
∴ is perpendicular to Y-axis if c = 0.