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Let T and C respectively, be the transverse and conjugate axes of the hyperbola $$16x^2 - y^2 + 64x + 4y + 44 = 0$$. Then the area of the region above the parabola $$x^2 = y + 4$$, below the transverse axis T and on the right of the conjugate axis C is:
We need to find the area of a region defined by the hyperbola's axes and a parabola.
Rewrite the hyperbola in standard form
$$ 16x^2 - y^2 + 64x + 4y + 44 = 0 $$
$$ 16(x^2 + 4x) - (y^2 - 4y) + 44 = 0 $$
$$ 16(x^2 + 4x + 4) - (y^2 - 4y + 4) + 44 - 64 + 4 = 0 $$
$$ 16(x + 2)^2 - (y - 2)^2 = 16 $$
$$ \frac{(x+2)^2}{1} - \frac{(y-2)^2}{16} = 1 $$
Center: $$(-2, 2)$$, $$a = 1$$, $$b = 4$$.
Identify axes
Transverse axis T: $$y = 2$$ (horizontal line through center)
Conjugate axis C: $$x = -2$$ (vertical line through center)
Set up the region
Region: above parabola $$x^2 = y + 4$$ (i.e., $$y = x^2 - 4$$), below transverse axis $$y = 2$$, and to the right of conjugate axis $$x = -2$$.
Find intersection points
Parabola meets $$y = 2$$: $$x^2 = 6$$, so $$x = \sqrt{6}$$ (taking $$x > -2$$).
Also $$x = -\sqrt{6} \approx -2.449 < -2$$.
Parabola meets $$x = -2$$: $$y = 4 - 4 = 0$$.
So the region is bounded by $$x = -2$$ (left), $$y = 2$$ (top), and $$y = x^2 - 4$$ (bottom), from $$x = -2$$ to $$x = \sqrt{6}$$.
Compute the area
$$ A = \int_{-2}^{\sqrt{6}} [2 - (x^2 - 4)]\,dx = \int_{-2}^{\sqrt{6}} (6 - x^2)\,dx $$
$$ = \left[6x - \frac{x^3}{3}\right]_{-2}^{\sqrt{6}} $$
At $$x = \sqrt{6}$$: $$6\sqrt{6} - \frac{6\sqrt{6}}{3} = 6\sqrt{6} - 2\sqrt{6} = 4\sqrt{6}$$
At $$x = -2$$: $$-12 + \frac{8}{3} = -\frac{28}{3}$$
$$ A = 4\sqrt{6} - \left(-\frac{28}{3}\right) = 4\sqrt{6} + \frac{28}{3} $$
This matches Option 2: $$4\sqrt{6} + \frac{28}{3}$$.
The answer is $$\boxed{4\sqrt{6} + \frac{28}{3}}$$.
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