Exercise · ZW-LINEAR-INDEPENDENCE-001 · ★☆☆ Basic
Are \((1,2)\) and \((2,4)\) linearly independent ?
Choose one option.
A Yes, because they are different vectors B No, because \((2,4)=2(1,2)\) C Yes, because their sum is \((3,6)\) D No, because neither is the zero vector
Show answer B. No, because \((2,4)=2(1,2)\)
← Back to the question
Explanation Since \((2,4)=2(1,2)\), there is the nontrivial combination \(2(1,2)-(2,4)=0\); being different is not enough.
A set of vectors is linearly independent if the only linear combination of them that gives the zero vector is the one with all coefficients equal to zero.
\[c_1v_1+\cdots+c_kv_k=0\ \Rightarrow\ c_1=\cdots=c_k=0\]
More practice problems: linear independence ZW-LINEAR-INDEPENDENCE-002 Which of these subsets of ℝ^2 is linearly independent?ZW-LINEAR-INDEPENDENCE-003 A set containing the zero vector is always:ZW-LINEAR-INDEPENDENCE-004 For v_1=(1,2,3) and v_2=(2,4,6), which coefficients (c_1,c_2), not both zero, give c_1v_1+c_2v_2=0?ZW-LINEAR-INDEPENDENCE-005 For which value of k are (1,2) and (3,k) linearly dependent?ZW-LINEAR-INDEPENDENCE-006 The vectors (1,0,1), (0,1,1) and (1,1,2) are:ZW-LINEAR-INDEPENDENCE-007 A set of 4 vectors in ℝ^3 is always:ZW-LINEAR-INDEPENDENCE-008 For which value of k are (1,0,2), (0,1,1) and (1,1,k) linearly dependent?ZW-LINEAR-INDEPENDENCE-009 If u and v are linearly independent, which of these sets is dependent?