${\displaystyle 𝑎=𝑏}$ $𝑎=𝑏$ $𝑎=𝑏$ $𝑎=𝑏$ $$\left(\begin{array}{ccc}1& 0& 0\\ 0& 1& 0\\ 0& 0& 1\end{array}\right)=\{\begin{array}{cc}1\hfill & \text{if <math xmlns:tex="http://typesetting.eu/2021/LuaMathML" xmlns="http://www.w3.org/1998/Math/MathML"> <mi>𝑎</mi> <mo lspace="0.278em" rspace="0.278em" tex:class="rel">=</mo> <mi>𝑏</mi> </math>}\hfill \\ 2\hfill & \text{else}\hfill \end{array}$$ $$𝑥=\frac{-𝑏\pm \sqrt{{𝑏}^2-4𝑎𝑐}}{2𝑎}.$$ $$\sum _{𝑎}\underset{\_}{𝑐}\stackrel{.}{𝑏}{𝑐}^{\mathrm{\prime }}$$ $$\begin{array}{}\text{(1)}& 𝑎𝑏𝑐& =𝑑𝑒𝑓& {𝑒}^{\mathrm{i}𝜋}& =-1\text{(2)}& (1+2& =3)& & \text{(3)}& 5& & & \end{array}$$ $\mathrm{s}\mathrm{i}\mathrm{n}(𝑥)-\mathrm{s}\mathrm{i}\mathrm{n}(𝑥+2𝜋)=0$