Vector Mag: When Does u+w > mag(u)+mag(w)?

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The discussion explores the conditions under which the magnitude of the sum of two vectors, u and w, exceeds the sum of their individual magnitudes. It highlights the relationship between vector addition and triangle inequality, suggesting that the scenario occurs when the vectors are aligned in the same direction. The conversation emphasizes the importance of considering both parallel and antiparallel cases for a comprehensive understanding. Participants are encouraged to visualize the vectors as sides of a triangle to grasp the concept better. Understanding these geometric relationships is key to solving the problem effectively.
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Homework Statement


If a vector "u" is added to a vector "w", under what circumstances will the value of mag(u+w) ever be greater than mag(u)+mag(w)?

Homework Equations


Magnitude = Sqrt( (Sum of x components)^2 + (sum of y components)^2 )

The Attempt at a Solution



I really, have no idea where to begin... I guess I could set up an equation and try to solve for the variables... Could someone point me in the right direction?

Thanks for all the help!
 
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Think of your two vectors as representing two sides of a triangle, and their sum as the third side of the triangle. What is the longest possible length that that third side in terms of the lengths of sides u and w?

Note: You either have to extend the concept of triangle here a bit to accommodate the cases where u and v are parallel or antiparallel, or you can cover those as special cases.
 
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