Q. All four of the vectors below are added to vector E. Positive angles are measured counter-clockwise from the x axis.(adsbygoogle = window.adsbygoogle || []).push({});

A = 2 m î + 3 m ĵ

B = -7 m î -10 m ĵ

C = 3 m at 62 °

D = 8 m at -226 °

a) What is C·D?

C.D = |C| |D| cos theta

I did this.

3* cos 62 + 8 cos -226 , but the answer is wrong

b) Vector F is the cross product of vectors A and B (= A X B).

What is the z component of vector F?

The answer is one, but how

F = A X B

Find the cross product by evaluating the determinant of vectors A & B.

Then what!!

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# Homework Help: Vector Addition

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