Lesson 12: Making Block Matrices in LATEX
$$xjkfdleft[xjkfdbegin{array}{c|c|c|c}A & Ab & xjkfdcdots & A^{n-1}bxjkfdend{array}xjkfdright]$$左右分块：
$$xjkfdleft[xjkfdbegin{array}{cccc|c}a_{11}&a_{12}&xjkfdcdots&a_{1n}&b_1xjkfdxjkfda_{21}&a_{22}&xjkfdcdots&a_{2n}&b_2xjkfdxjkfdxjkfdvdots&&xjkfdddots&xjkfdvdots&xjkfdvdotsxjkfdxjkfda_{n1}&a_{n2}&xjkfdcdots&a_{nn}&b_nxjkfdxjkfdxjkfdend{array}xjkfdright]$$四个对角：
$$C=xjkfdleft[xjkfdbegin{array}{c|c}A& B xjkfdxjkfd xjkfdhline C& Dxjkfdend{array}xjkfdright]$$