Question

If A = 2 i + j-k, B = i- j + 3k.
Find the value of A x B and A.B​

Answer 1

Explanation:

Let

a

=

i

+2

j

+3

k

b

=3

i

+

j

a

+

b

=

i

+2

j

+3

k

+3

i

+

j

a

+

b

=4

i

+3

j

+3

k

Sounitvectorinthedirectionof

a

+

b

∣

∣

∣

∣

a

+

b

∣

∣

∣

∣

=

4

2

+3

2

+3

2

=

16+9+9

=

34

sounitvectorinthedirectionof

a

+

b

is

=

34

4

i

+

34

3

j

+

34

3

k