Science:Math Exam Resources/Courses/MATH152/April 2016/Question A 18
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Question A 18 

Find a constant so that the following set of vectors is linearly dependent:

Make sure you understand the problem fully: What is the question asking you to do? Are there specific conditions or constraints that you should take note of? How will you know if your answer is correct from your work only? Can you rephrase the question in your own words in a way that makes sense to you? 
If you are stuck, check the hint below. Consider it for a while. Does it give you a new idea on how to approach the problem? If so, try it! 
Hint 

Consider the relation of matrix determinant and linear dependence . 
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Solution 

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Please rate my easiness! It's quick and helps everyone guide their studies. We write these three vectors as the column vectors of a matrix. The determinant of a matrix is zero if its column vectors are dependent. If we expand the first column to calculate the determinant, we have This implies Thus, 