If the system of linear equations
has a non-zero solution , then is equal to :
has a non-zero solution , then is equal to :
- (A)30
- (B)-10
- (C)10✓ Correct
- (D)-30
Answer: (C)
Solution
A non-trivial solution needs the coefficient determinant to vanish. Expanding gives , so . With , taking in the first two equations gives and , hence .
JEE Main · 2018 · 08 Apr 2018 · Offline · Single correct option