(a) Evaluate: \(\int \limits_1^2 (2x^3 – 4x + 3) dx\)
(b) Given that P\(^{-1}\) = \(\begin{pmatrix} -1 & 1 \\ 4 & -3 \end{pmatrix}\), find the matrix P.
Explanation
(a). They integrated the given function correctly to obtain (\(\frac{x^4}{2} - 2x^2 + 6x\)). Substituting the limits 2 and 1 for x and simplifying yielded 12 - \(\frac{9}{2}\) = 7\(\frac{1}{2}\)
(b). Find the determinant of which was P(\(^{-1}\))\(^{-1}\) = |P=\(^{-1}\)| (-3 x -1) - (4 x 1) = -1.
Using the concept of P(\(^{-1}\))\(^{-1}\) = P, then, P = -1 \(\begin{pmatrix} -3 & -1 \\ 4 & -3 \end{pmatrix}\) = \(\begin{pmatrix} 3 & 1 \\ 4 & 1 \end{pmatrix}\)