The pictures show parts of graphs of functions that are decreasing on the interval \([1;5]\). Choose the picture showing the part of the graph of the function \[f(x)=\frac{x+7}{x+1}.\]
The pictures show parts of graphs of functions that are increasing on the interval \([1;5]\). Choose the picture showing the part of the graph of the function \[f(x)=\frac{5x-1}{x+1}.\]
Determine the values of \( a \) and \( b \) (\( a \), \( b \in\mathbb{R} \)) such that the function
\[ f(x)=ax^3-2bx+2 \]
has a local extremum of \( 6 \) at \( x=-1 \).
Choose the graph of a function $f$ that satisfies
\begin{gather*}
f'(1) \text{ does not exist}; \\
f''(x) < 0 \text{ if } x < 1 ; \\
f''(x) < 0 \text{ if } x > 2; \\
f''(x) > 0 \text{ if } 1 < x < 2
\end{gather*}
($f'$ is the derivative of a function $f$, $f''$ is the second derivative of a function $f$).
Choose the graph of a function $f$ that satisfies
\begin{gather*}
f'(-2)=f'(0)=0; \\
f''(-2) < 0;\ f''(0) > 0
\end{gather*}
($f'$ is the derivative of the function $f$, $f''$ is the second derivative of the function $f$).