How to you find the sum of these vectors?

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1 Answer
Sep 8, 2017

From Polygon law of vector addition we know that:
If a number of vectors can be represented as sides of an open polygon taken in the same order, then the closing side of the polygon taken in the opposite order represents their resultant vector.

A corollary:

If a number of vectors are represented by the sides of a closed polygon taken in the same order, then, their resultant is zero.

In the given figure, #vecA# is identified as right most side.

Therefore, from the corollary we get
#vecA+vecB+vecC+vecD=0#