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\huge
$$\int\limits_a^b f(x)\,\mbox{d}x \;* \sum_{\gamma=x\frac{2}{\sqrt[5]{c+d}}}^{n}\;\approx{}\;\frac{\left({a \atop {b+1}}\right)}{\Big(x^2\big)^4}$$
\\
$$
\left(
\begin{array}{*{4}{c}}
a_{11} & a_{12} & \cdots & a_{1n} \\
\vdots & \vdots & \ddots & \vdots \\
a_{n1} & a_{n2} & \cdots & a_{nn} \\
\end{array}
\right)
$$