# VECTORS WHAT IS THE REASON FOR TO DEFINE a.b=|a||b| cos(a,b)

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In scalar multiplication we are considering only logical values and doing multiplication but here we are taking care of the direction of the force magnitude of the force applied to the body for the perfect accurate value which helps in making of the real world application.

here scalar values will not work for making any real thing, So in your question cos (a,b) suggests the resultant direction of the resultant force and |a||b| are the magnitude.

For more details on vector multiplication :: http://mathworld.wolfram.com/VectorMultiplication.html

Posted on Sep 20, 2008

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