heres the problem.(adsbygoogle = window.adsbygoogle || []).push({});

im supposed to use geometric definition to find. (i+J)cross(i-j)

I know: v x w=IIvIIIIwIISin[theta] and that The answer comes out to be -2k

But what i dont get is looking at the solution manual they show [theta]=pi/4 which i have know clue where that comes from.

I was thinking that i could use (v)dot(w) =Cos[theta] to get[theta] but that ends up being pi/2 not pi/4 like the solution manual says.

I think the solution maunual is wrong after futher review [Theta} should equal pi/2, not Pi/4

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# Homework Help: Cross product question.

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