Prove that the vectors 5a + 6b + 7c, 7a - 8b + 9c and 3a + 20b + 5c are linearly dependent vectors a, b, c being linearly independent vectors.
We know that if these vectors are linearly dependent , then we can express one of them as a linear combination of the other two.
Now let us assume that the given vector are coplanar, then we can write
Hence the given vectors are linearly dependent .
