Ответ:
0\\x-2\geq 0\end{array}\right\ \ \to \ \ x\geq 2\\\\x\in [\, 2\, ;+\infty \, )\ \ ;\ \ \ \ otvet:\ \#2\\\\\\9)\ \ f(x)=5+6x-x^2\ \ \to \ \ f'(x)=6-2x=0\ \ ,\ \ x=3\ \ ,\ \ \ otvet:\#4" alt="8)\ \ f(x)=\dfrac{1}{\sqrt{x-1}}+\sqrt{x-2}\ \ ,\ \ \ ODZ:\ \left\{\begin{array}{ccc}x-1>0\\x-2\geq 0\end{array}\right\ \ \to \ \ x\geq 2\\\\x\in [\, 2\, ;+\infty \, )\ \ ;\ \ \ \ otvet:\ \#2\\\\\\9)\ \ f(x)=5+6x-x^2\ \ \to \ \ f'(x)=6-2x=0\ \ ,\ \ x=3\ \ ,\ \ \ otvet:\#4" align="absmiddle" class="latex-formula">