8√3
24
We are asked to evaluate the limit:
\( \lim\limits_{t \rightarrow 0} \frac{\tan^2\left(\frac{\pi}{3} + t\right) - 3}{t} \).
We begin by expanding \( \tan\left(\frac{\pi}{3} + t\right) \) using the tangent addition formula:
\( \tan\left(\frac{\pi}{3} + t\right) = \frac{\tan\left(\frac{\pi}{3}\right) + \tan(t)}{1 - \tan\left(\frac{\pi}{3}\right)\tan(t)} \).
Since \( \tan\left(\frac{\pi}{3}\right) = \sqrt{3} \), we have:
\( \tan\left(\frac{\pi}{3} + t\right) = \frac{\sqrt{3} + \tan(t)}{1 - \sqrt{3}\tan(t)} \).
Next, we square both sides to find \( \tan^2\left(\frac{\pi}{3} + t\right) \):
\( \tan^2\left(\frac{\pi}{3} + t\right) = \left( \frac{\sqrt{3} + \tan(t)}{1 - \sqrt{3}\tan(t)} \right)^2 \).
Now, we compute the limit:
\( \lim\limits_{t \rightarrow 0} \frac{\tan^2\left(\frac{\pi}{3} + t\right) - 3}{t} \).
We can directly differentiate the numerator and denominator using the derivative approach. The derivative of the numerator at \( t = 0 \) gives us the required limit:
Using a standard result or applying L'Hopital's Rule, we find that the value of the limit is:
The correct answer is \( 24 \).
Let $\left\lfloor t \right\rfloor$ be the greatest integer less than or equal to $t$. Then the least value of $p \in \mathbb{N}$ for which
\[ \lim_{x \to 0^+} \left( x \left\lfloor \frac{1}{x} \right\rfloor + \left\lfloor \frac{2}{x} \right\rfloor + \dots + \left\lfloor \frac{p}{x} \right\rfloor \right) - x^2 \left( \left\lfloor \frac{1}{x^2} \right\rfloor + \left\lfloor \frac{2}{x^2} \right\rfloor + \dots + \left\lfloor \frac{9^2}{x^2} \right\rfloor \right) \geq 1 \]
is equal to __________.
If \( f(x) \) is defined as follows:
$$ f(x) = \begin{cases} 4, & \text{if } -\infty < x < -\sqrt{5}, \\ x^2 - 1, & \text{if } -\sqrt{5} \leq x \leq \sqrt{5}, \\ 4, & \text{if } \sqrt{5} \leq x < \infty. \end{cases} $$ If \( k \) is the number of points where \( f(x) \) is not differentiable, then \( k - 2 = \)