Use the Inverse Formula $$A ^ { - 1 } = \frac { 1 } { a d - b c } \left[ \begin{array} { c c } d & - b \\- c & a\end{array} \right]$$

question 5

Multiple Choice

Use the inverse formula $$A ^ { - 1 } = \frac { 1 } { a d - b c } \left[ \begin{array} { c c } d & - b \\- c & a\end{array} \right]$$ to find the inverse of the 2×2 matrix (if it exists) .​ $$\left[ \begin{array} { c c } 6 & 7 \\- 5 & 13\end{array} \right]$$ ​

• A)​ \[\frac { 1 } { 113 } \left[ \begin{array} { c c }
• 13 & - 7 \\
• 5 & 6
• \end{array} \right]\]
• B)​ \[\frac { 1 } { 113 } \left[ \begin{array} { c c }
• - 13 & 7 \\
• 5 & - 6
• \end{array} \right]\]
• C)​ \[\frac { 1 } { 113 } \left[ \begin{array} { c c }
• - 13 & - 7 \\
• 5 & 6
• \end{array} \right]\]
• D)​ \[\frac { 1 } { 113 } \left[ \begin{array} { c c }
• 13 & 7 \\
• 5 & 6
• \end{array} \right]\]
• E)​ \[\frac { 1 } { 113 } \left[ \begin{array} { c c }
• - 13 & - 7 \\
• - 5 & - 6
• \end{array} \right]\]

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Definitions:

Genetic Drift

A mechanism of evolution that involves random changes in the frequency of alleles within a population over time.

McDonald-Kreitman Test

A method used in molecular evolution to compare the ratio of non-synonymous to synonymous substitutions in a gene between species, assessing natural selection.

Homologous Gene

Genetic sequences that are shared by different species and have been inherited from a common ancestor.