\[\boxed{\text{396\ (396).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\textbf{а)}\ \sqrt{a^{2}} = |a| = a;при\ \ a > 0\]
\[\textbf{б)}\ \sqrt{n^{2}} = |n| = - n;при\ \ n < 0\]
\[\textbf{в)}\ 3\sqrt{c^{2}} = 3 \cdot |c| = 3c;\ \]
\[при\ \ c > 0\]
\[3\sqrt{c^{2}} = 3 \cdot |0| = 0;при\ \ \ \ \ c = 0\]
\[\textbf{г)} - 5\sqrt{y^{2}} = - 5 \cdot |y| = - 5y;\ \]
\[при\ \ y > 0\]
\[\textbf{д)}\ \sqrt{36x^{2}} = 6 \cdot |x| = 6 \cdot ( - x) =\]
\[= - 6x;\ при\ \ x < 0\]
\[\sqrt{36x^{2}} = 0;при\ \ \ \ x = 0\]
\[\textbf{е)} - \sqrt{9y^{2}} = - 3 \cdot |y| =\]
\[= - 3 \cdot ( - y) = 3y;\ при\ \ y < 0\]
\[\textbf{ж)} - 5 \cdot \sqrt{4x^{2}} = - 5 \cdot 2 \cdot |x| =\]
\[= - 10x;\ при\ \ x > 0\]
\[- 5\sqrt{4x^{2}} = 0;\ при\ \ \ \ \ \ \ x = 0\]
\[\textbf{з)}\ 0,5 \cdot \sqrt{16a^{2}} = 0,5 \cdot 4 \cdot |a| =\]
\[= 2 \cdot ( - a) = - 2a;при\ \ a < 0\]