Question

five vector are respresented by sides of of a closed polygon taken in the same order make use of triangle law to prove that their resultant is zero

Answer 1

Let's start small. Let's look at addition of two vectors. We add them using the triangle law of vector addition. What does this law say? It says “The resultant of two vectors is the vector from the tail of the first vector to the head of the second one , when we align the tail of the second one to the head of the first vector “. For reference, see the picture attached here :

So, all you need to do to find the resultant is arrange your vectors in a chain fashion without changing their directions, and trace the vectors one by one. The vector from your starting point to your ending point will be the resultant!

Coming to your problem now, if the vectors form a polygon, then do the same as above. Trace each vector one by one. If the vectors form a polygon, then you will finally end up exactly where you began! So, your starting point is the same as your ending point. This means that your resultant vector is a zero vector, because if starting and ending points are the same, then the vector between them has no length. So, in such a case, the resultant will be a zero vector!

Answer 2

нєу тнєяє ιѕ уσυя αиѕωєя
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αв =σα+σв = -σα+σв
в¢= вσ+σ¢ = -вσ+σ¢
¢∂ = ¢σ+ σ∂
∂є = ∂σ+ σє
єα = єα + αє
α∂∂ αℓℓ...
αв+ в¢+ ¢∂+ ∂є+ єα = 0