Coplanar and Linear dependency.

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Homework Statement


Prove that vectors u, v, w are coplanar if and only if vectors u, v and w are linearly dependent.\overline{v}_{3}=\alpha\overline{v}_{1}+\beta\overline{v}_{2} (Coplanar Vector Property)
\alpha\overline{v}_{1}+\beta\overline{v}_{2}+\gamma\overline{v}_{3}=\overline{0} (linearly dependent vector property)
 
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jrotmensen said:

Homework Statement


Prove that vectors u, v, w are coplanar if and only if vectors u, v and w are linearly dependent.


\overline{v}_{3}=\alpha\overline{v}_{1}+\beta\overline{v}_{2} (Coplanar Vector Property)
\alpha\overline{v}_{1}+\beta\overline{v}_{2}+\gamma\overline{v}_{3}=\overline{0} (linearly dependent vector property)
State the entire properties! What you have are equations, not properties.

"Three vectors, v_1, v_2, and v_3 are coplanar if and only if
\overline{v}_{3}=\alpha\overline{v}_{1}+\beta\overline{v}_{2}
or
\overline{v}_{1}=\alpha\overline{v}_{2}+\beta\overline{v}_{3}
or
\overline{v}_{2}=\alpha\overline{v}_{1}+\beta\overline{v}_{3}
for some numbers \alpha and \beta"

"Three vectors, v_1, v_2, and v_3 are dependent if \alpha\overline{v}_{1}+\beta\overline{v}_{2}+\gamma\overline{v}_{3}=\overline{0}
with not all of \alpha, \beta, \gamma equal to 0."

Suppose \vec{v_1}, \vec{v_2}, and \vec{v_3} are planar. Subtract the right side of that equation from both sides.

Suppose \vec{v_1}, \vec{v_2}, and \vec{v_3} are dependent. Solve that equation for one of the vectors.
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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