# [SOLVED] Find the vector, not with determinants, but by using properties of cross products. k × (i − 4j)?

Find the vector, not with determinants, but by using properties of cross products. k × (i − 4j)?

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we know that

i x j = k,

j x k = i,

k x i = j.

Also we know anticommutativity of the cross product:

a x b = - b x a

Then k x i - 4 k x j = j + 4i

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Look at the image in link first.

k × (i − 4j)

= k x i - k x 4j

= k x i - 4(k x j)

= j - 4(-i)

= j + 4i

(which we normally wrte as 4i + j)

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat.