In the usual notation,the value of $\Delta \nabla$ is equal to

Which of the following statements is true for the function $f(x) = \begin{cases} \sqrt{x} & x \ge 1 \\ x^3 & 0 \le x < 1 \\ \frac{x^3}{3} - 4x & x < 0 \end{cases}$

The function defined by $f(x) = \begin{cases} |x - 3|, & x \ge 1 \\ \frac{1}{4}x^2 - \frac{3}{2}x + \frac{13}{4}, & x < 1 \end{cases}$ is

Let $f(x) = \lim_{n}$ ${\rightarrow \infty} \left( \frac{n^n(x+n)(x+\frac{n}{2}) \cdots (x+\frac{n}{n})}{n!(x^2+n^2)(x^2+\frac{n^2}{4}) \cdots (x^2+\frac{n^2}{n^2})} \right)^{\frac{x}{n}}$,for all $x > 0$. Then
$(A)$ $f(\frac{1}{2}) \geq f(1)$
$(B)$ $f(\frac{1}{3}) \leq f(\frac{2}{3})$
$(C)$ $f^{\prime}(2) \leq 0$
$(D)$ $\frac{f^{\prime}(3)}{f(3)} \geq \frac{f^{\prime}(2)}{f(2)}$

Let $f$ be a differentiable function and the equation of the normal to the graph of $y = f(x)$ at $x = 3$ is $3y = x + 18$. If $L = \mathop {\lim }\limits_{x \to 1} \frac{{f\left( {3 + {{\left( {4{{\tan }^{ - 1}}x - \pi } \right)}^2}} \right) - f\left( {3 + {{\left( {f\left( 3 \right) - x - 6} \right)}^2}} \right)}}{{{{\sin }^2}\left( {x - 1} \right)}}$,then:

Let $f$ be a differentiable function on $\mathbb{R}$ such that $f(2) = 1$ and $f'(2) = 4$. If $\lim_{x \rightarrow 0} (f(2+x))^{3/x} = e^\alpha$,then the number of times the curve $y = 4x^3 - 4x^2 - 4(\alpha - 7)x - \alpha$ intersects the $x$-axis is: