## anonymous one year ago Topic: Projections and Minimum Distance Use a projection to find the distance from the point to the plane Q(0, 2, -1), plane $$\sf 2x_1-x_3=5$$.

1. anonymous

i know that normal vector would be.. <2,0,-1>

2. anonymous

and then...pick a point from the plane.. when x1 is 0, then x3 must be equal to -5.. so my point P would be P<0,0,-5>

3. anonymous

then what?

4. anonymous

PQ would be <0-0, 2-0, -1+5>= <0,2,4>

5. anonymous

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6. anonymous

Projection of PQ on n, is.. $\frac{ |PQ • n| }{ |n|}$

7. anonymous

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