\[1)\ y = \cos^{2}{3x};\]
\[y^{'}(x) = 2\cos{3x} \bullet 3 \bullet \left( - \sin{3x} \right) =\]
\[= - 6\sin{3x}\cos{3x} = - 3\sin{6x}.\]
\[2)\ y = tg^{2}\frac{x}{2};\]
\[y^{'}(x) = 2\ tg\frac{x}{2} \bullet \frac{1}{2} \bullet \frac{1}{\cos^{2}\frac{x}{2}} =\]
\[= \frac{\sin\frac{x}{2}}{\cos^{3}\frac{x}{2}}.\]
\[3)\ y = \sin\left( 2x^{2} - 3x \right);\]
\[y^{'}(x) =\]
\[= (2 \bullet 2x - 3) \bullet \cos\left( 2x^{2} - 3x \right) =\]
\[= (4x - 3)\cos\left( 2x^{2} - 3x \right).\]
\[4)\ y = \cos\left( x + 2x^{3} \right);\]
\[y^{'}(x) =\]
\[= \left( 1 + 2 \bullet 3x^{2} \right) \bullet \left( - \sin\left( x + 2x^{3} \right) \right) =\]
\[= - \left( 1 + 6x^{2} \right)\sin\left( x + 2x^{3} \right).\]
\[5)\ y = e^{\text{tg\ x}};\]
\[y^{'}(x) = \frac{1}{\cos^{2}x} \bullet e^{\text{tg\ x}} = \frac{e^{\text{tg\ x}}}{\cos^{2}x}.\]
\[6)\ y = \cos\left( e^{x} \right);\]
\[y^{'}(x) = e^{x} \bullet \left( - \sin e^{x} \right) =\]
\[= - e^{x} \bullet \sin e^{x}.\]
\[7)\ y = 3^{x^{2}};\]
\[y^{'}(x) = 2x \bullet 3^{x^{2}} \bullet \ln 3.\]
\[8)\ y = 2^{\cos x};\]
\[y^{'}(x) = - \sin x \bullet 2^{\cos x} \bullet \ln 2.\]