Suppose we have two vectors v=[13] and w=[42].
What is the meaning of v+w and how do we calculate it?
Visually, we can add vectors tip-to-tail as such:

We can see from the plot that v+w= [55].
Mathematically, we add vectors component by component, i.e.
v+w =[13]+ [42]=[1+43+2] =[55].
In general, for vectors v=[v1v2] and w=[w1w2] we have:
v+w =[v1v2]+ [w1w2]=[v1+w1v2+w2 ].
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