Question

The volume of the parallelopiped whose conterminous edges are $i - j + k,2i - 4j + 5k$and $3i - 5j + 2k$ is

• A. 4
• B. 3
• C. 2
• D. 8

Answer 1

Answer: (D)

8

Answer 2

Volume of parallelopiped $V = \lbrack\mathbf{abc}\rbrack$

$\therefore V = \left| \begin{matrix} 1 & - 1 & 1 \\ 2 & - 4 & 5 \\ 3 & - 5 & 2 \end{matrix} \right|$

$V = 1( - 8 + 25) + 1(4 - 15) + 1( - 10 + 12)$

V $= 17 - 11 + 2 = 8$ unit.