1. **Problem Statement:**
Find the inverse of matrix $$P = \begin{pmatrix}8 & 5 \\ 6 & 9\end{pmatrix}$$.
2. **Formula for Inverse of a 2x2 Matrix:**
For a matrix $$A = \begin{pmatrix}a & b \\ c & d\end{pmatrix}$$, the inverse $$A^{-1}$$ is given by:
$$
A^{-1} = \frac{1}{ad - bc} \begin{pmatrix} d & -b \\ -c & a \end{pmatrix}
$$
provided that the determinant $$ad - bc \neq 0$$.
3. **Calculate the determinant of P:**
$$
\det(P) = (8)(9) - (5)(6) = 72 - 30 = 42
$$
Since $$42 \neq 0$$, the inverse exists.
4. **Apply the formula:**
$$
P^{-1} = \frac{1}{42} \begin{pmatrix} 9 & -5 \\ -6 & 8 \end{pmatrix} = \begin{pmatrix} \frac{9}{42} & \frac{-5}{42} \\ \frac{-6}{42} & \frac{8}{42} \end{pmatrix}
$$
5. **Simplify fractions:**
$$
P^{-1} = \begin{pmatrix} \frac{3}{14} & -\frac{5}{42} \\ -\frac{1}{7} & \frac{4}{21} \end{pmatrix}
$$
**Final answer:**
$$
P^{-1} = \begin{pmatrix} \frac{3}{14} & -\frac{5}{42} \\ -\frac{1}{7} & \frac{4}{21} \end{pmatrix}
$$
Matrix Inverse
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.