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Mathematics · Ch 5 — Vectors

Vector in Two Dimensions (2-D)

5.1.7

Vector in Two Dimensions (2-D)

Restricting to a single plane, the set of all combinations xaˉ+ybˉx\bar a+y\bar b (for real x,yx,y) of two

non-collinear vectors aˉ,bˉ\bar a,\bar b sweeps out the entire plane; aˉ,bˉ\bar a,\bar b are then called the

generators of that plane, and {aˉ,bˉ}\{\bar a,\bar b\} its basis. The most useful basis is the pair of

standard unit vectors: taking M=(1,0)M=(1,0) on the X-axis and N=(0,1)N=(0,1) on the Y-axis, define

ı^=OM→\hat\imath=\overrightarrow{OM} and ȷ^=ON→\hat\jmath=\overrightarrow{ON}. Then any vector OP→\overrightarrow{OP}

to a point P=(x,y)P=(x,y) is xı^+yȷ^x\hat\imath+y\hat\jmath -- for instance, the point P=(3,4)P=(3,4) gives …