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If $$\alpha = \lim_{x \to \pi/4} \frac{\tan^3 x - \tan x}{\cos x + \frac{\pi}{4}}$$ and $$\beta = \lim_{x \to 0} \cos x^{\cot x}$$ are the roots of the equation, $$ax^2 + bx - 4 = 0$$, then the ordered pair $$a, b$$ is:
The limit is given by:
$$\alpha = \lim_{x \to \pi/4} \frac{\tan^3 x - \tan x}{\cos(x + \pi/4)}$$
Substituting $$x = \pi/4$$ gives the indeterminate form $$\frac{1-1}{0} = \frac{0}{0}$$. We can apply L'Hôpital's Rule:
$$\alpha = \lim_{x \to \pi/4} \frac{3\tan^2 x \sec^2 x - \sec^2 x}{-\sin(x + \pi/4)}$$
Now, substitute $$x = \pi/4$$:
$$\alpha = \frac{3(1)^2(\sqrt{2})^2 - (\sqrt{2})^2}{-\sin(\pi/4 + \pi/4)} = \frac{3(2) - 2}{-\sin(\pi/2)} = \frac{6 - 2}{-1} = -4$$
The limit is given by:
$$\beta = \lim_{x \to 0} (\cos x)^{\cot x}$$
This is of the form $$1^\infty$$. We use the formula $$\lim_{x \to a} [f(x)]^{g(x)} = e^{\lim_{x \to a} g(x)[f(x) - 1]}$$:
$$\beta = e^{\lim_{x \to 0} \cot x (\cos x - 1)} = e^{\lim_{x \to 0} \frac{\cos x - 1}{\tan x}}$$
Applying L'Hôpital's Rule to the exponent:
$$\lim_{x \to 0} \frac{-\sin x}{\sec^2 x} = \frac{0}{1} = 0$$
Thus, $$\beta = e^0 = 1$$.
The roots of the equation $$ax^2 + bx - 4 = 0$$ are $$\alpha = -4$$ and $$\beta = 1$$.
Using the properties of roots:
The values are $$a = 1$$ and $$b = 3$$. The ordered pair $$(a, b)$$ is (1, 3).
Correct Option: C
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