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If c⃗ =a⃗ b⃗ , can c=a b ? show how or explain why not.

User Ferrybig
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Final answer:

The equation c⟳ =a⟳ b⟳ does not necessarily mean that c = a b without specifying the type of vector multiplication. For a dot product, c equals the product of vectors' magnitudes and the cosine of the angle between them, while for a cross product, it equals the product of vectors' magnitudes and the sine of the angle between them, thus providing different results.

Step-by-step explanation:

The question relates to whether the product of two vectors c⟳ =a⟳ b⟳ implies that their magnitudes multiply to give c = a b. In vector mathematics, there are two main types of multiplication: the dot product (scalar product) and the cross product (vector product). The dot product of two vectors results in a scalar (a number), while the cross product results in another vector. Therefore, the notation c⟳ =a⟳ b⟳ is ambiguous without specifying whether it refers to the dot or cross product.

If c⟳ = a⟳ · b⟳ (dot product), then c is indeed the product of the magnitudes of vectors a and b multiplied by the cosine of the angle between them, hence, c = |a⟳| |b⟳| cos(θ). On the other hand, if c⟳ = a⟳ × b⟳ (cross product), then c⟳ is a vector that is orthogonal to both a⟳ and b⟳ and its magnitude is equal to the area of the parallelogram that a⟳ and b⟳ span, which is c = |a⟳| |b⟳| sin(θ). Hence, without clarity on the type of vector product, one cannot directly conclude that c = a b.

User Amandeep Chugh
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