Let A = $\displaystyle

\begin{array}{c}\ \\ \\ \end{array}\;\begin{vmatrix}\;a & b & c \;\\\;p & q & q \;\\\;u & v & w\end{vmatrix}

$

and assume that det A = 3.

Compute:

det(2c^-1) where C = $\displaystyle

\begin{array}{c}\ \\ \\ \end{array}\;\begin{vmatrix}\;2p & -a+u & 3u \;\\\;2q & -b+v & 3v \;\\\;2r & -c+w & 3w\end{vmatrix}

$

I'm getting an answer of 1/3, which is wrong. The answer is 9/4.

The troubles I'm having you can read about right

HERE. I know how to do everything, but I'm obviously just making a small mistake.

One specific question I would like to ask, is how do I remove the 2 from inside the det() brackets? I haven't been shown an example of that, and can't find one.

Thanks!