Question

Given a = 2i+j – 2k
b= -1 – 7j+k
Find a x b

Answer 1

Explanation:

a = 2i + j - k

b = -1 -7j + k

a × b = (2i + j - k) (-1 + 7j + k)

-2i + 14ij + 2ik - j + 7j^2 + jk + k -7jk - k^2

-2i + 14ij + 2ik -j +7j^2 +jk - 7jk + k - k^2

-2i + 14ij + 2ik - j +7j^2 - 6jk + k - k^2