Question

If two vector 2i+aj and i+2j are perpendicular to each other than a=?

Answer 1

Answer:

they are perpendicular so dot product is 0

so by doing dot product we get the equation

2+2a=0

2=-2a

a=-1

Answer 2

Answer:

-1

Explanation:

2+ 2a = 0

a = -1