for each expression, determine whether or not it makes sense..explain a*(b*c) ..the back of the book says this doesn't make sense but i don't know why..
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you can aonly take the dot product of a vector with a vector a*(b*c) b*c is a scalar (number) so you can't take the dot product of the vector a with a nunber
thanks so its the same thing with (a*b)/c then? because a*b is a number
no --- iit makes no sense because you can't divide by a vector-- there is no such operation. if c were a constant(a*b)/c is just a number over a number which would makes sense
ohh okay..so my last one is (the magnitude of a)^2 * b - (a*b)^2 *a
Same reason as the first (the magnitude of a)^2 * b - (a*b)^2 *a (the magnitude of a)^2 is a scalar (a*b)^2 is a scalar again you can't take the dot product of a scalar and a vector
the back of the book says its right though..hmm. oh well. thank you for all of your help with everything!! youre the best
you can take a scalar times a vector but not the dot product of a scalar with a vector so if the question was (|a|^2)b without the dot it makes sense Similarly[(a*b)^2]a would make sense if you are not talking about the dot product
thank you!
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