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If $\frac{\pi}{4} + \sum_{p=1}^{11} \tan^{-1} \left( \frac{2^{p-1}}{1 + 2^{2p-1}} \right) = \alpha$, then $\tan \alpha$ is equal to _________.

Solving for tan(alpha) in Inverse Trigonometric Sum

The problem requires finding the value of $\tan \alpha$, where $\alpha$ is defined by the equation:

$ \alpha = \frac{\pi}{4} + \sum_{p=1}^{11} \tan^{-1} \left( \frac{2^{p-1}}{1 + 2^{2p-1}} \right) $

We will simplify the summation term first.

Simplifying the Inverse Tangent Sum

Recall the inverse tangent subtraction identity:

$ \tan^{-1} x - \tan^{-1} y = \tan^{-1} \left( \frac{x-y}{1+xy} \right) $

We can rewrite the term inside the summation:

$ \frac{2^{p-1}}{1 + 2^{2p-1}} = \frac{2^p - 2^{p-1}}{1 + 2^p \cdot 2^{p-1}} $

Here, let $x = 2^p$ and $y = 2^{p-1}$. Applying the identity, the summation term becomes:

$ \tan^{-1} \left( \frac{2^p - 2^{p-1}}{1 + 2^p \cdot 2^{p-1}} \right) = \tan^{-1}(2^p) - \tan^{-1}(2^{p-1}) $

The summation is a telescoping series:

$ \sum_{p=1}^{11} (\tan^{-1}(2^p) - \tan^{-1}(2^{p-1})) $

Expanding the sum:

  • $p=1: \tan^{-1}(2^1) - \tan^{-1}(2^0)$
  • $p=2: \tan^{-1}(2^2) - \tan^{-1}(2^1)$
  • ...
  • $p=11: \tan^{-1}(2^{11}) - \tan^{-1}(2^{10})$

After cancellation, the sum simplifies to:

$ \tan^{-1}(2^{11}) - \tan^{-1}(2^0) = \tan^{-1}(2048) - \tan^{-1}(1) $

Calculating alpha

Substitute the simplified sum back into the equation for $\alpha$:

$ \alpha = \frac{\pi}{4} + (\tan^{-1}(2048) - \tan^{-1}(1)) $

Since $\frac{\pi}{4} = \tan^{-1}(1)$, we have:

$ \alpha = \tan^{-1}(1) + \tan^{-1}(2048) - \tan^{-1}(1) $ $ \alpha = \tan^{-1}(2048) $

Finding tan(alpha)

The final step is to find the tangent of $\alpha$:

$ \tan \alpha = \tan(\tan^{-1}(2048)) $ $ \tan \alpha = 2048 $
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Similar Questions

  1. The number of solutions of $\tan^{-1} 4x + \tan^{-1} 6x = \frac{\pi}{6}$, where $-\frac{1}{2\sqrt{6}} < x < \frac{1}{2\sqrt{6}}$, is equal to
  2. Let $\cos(\alpha + \beta) = -\frac{1}{10}$ and $\sin(\alpha - \beta) = \frac{3}{8}$, where $0 < \alpha < \frac{\pi}{3}$ and $0 < \beta < \frac{\pi}{4}$. If $\tan 2\alpha = \frac{3(1 - r\sqrt{5})}{\sqrt{11}(s + \sqrt{5})}, r, s \in \mathbb{N}$, then $r+s$ is equal to ________.

  3. The number of elements in the set $\{x \in [0, 180^\circ] : \tan(x + 100^\circ) = \tan(x + 50^\circ) \tan x \tan(x - 50^\circ)\}$ is _______.
  4. Considering the principal values of inverse trigonometric functions, the value of the expression $\tan\left(2\sin^{-1}\left(\frac{2}{\sqrt{13}}\right) - 2\cos^{-1}\left(\frac{3}{\sqrt{10}}\right)\right)$ is equal to :

  5. Number of solutions of $\sqrt{3}\cos 2\theta + 8\cos \theta + 3\sqrt{3} = 0, \theta \in [-3\pi, 2\pi]$ is :
  6. Let $\alpha$ and $\beta$ respectively be the maximum and the minimum values of the function $f(\theta) = 4\left(\sin^4\left(\frac{7\pi}{2} - \theta\right) + \sin^4(11\pi + \theta)\right) - 2\left(\sin^6\left(\frac{3\pi}{2} - \theta\right) + \sin^6(9\pi - \theta)\right), \theta \in \mathbf{R}$. Then $\alpha + 2\beta$ is equal to :
  7. The vertices B and C of a triangle ABC lie on the line $\frac{x}{1} = \frac{1 - y}{-2} = \frac{z - 2}{3}$. The coordinates of A and B are $(1, 6, 3)$ and $(4, 9, \alpha)$ respectively and C is at a distance of 10 units from B. The area (in sq. units) of $\Delta ABC$ is :
  8. The sum of all the integral values of $p$ such that the equation $3\sin^2 x + 12\cos x - 3 = p$, $x \in \mathbb{R}$, has at least one solution, is:
  9. If $\text{S} = \left\{\theta \in [-\pi, \pi] : \cos\theta \cos\frac{5\theta}{2} = \cos 7\theta \cos\frac{7\theta}{2}\right\}$, then $\text{n(S)}$ is equal to ___________.
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Important Questions from Trigonometry

  1. The number of solutions of $\tan^{-1} 4x + \tan^{-1} 6x = \frac{\pi}{6}$, where $-\frac{1}{2\sqrt{6}} < x < \frac{1}{2\sqrt{6}}$, is equal to
  2. Let $\cos(\alpha + \beta) = -\frac{1}{10}$ and $\sin(\alpha - \beta) = \frac{3}{8}$, where $0 < \alpha < \frac{\pi}{3}$ and $0 < \beta < \frac{\pi}{4}$. If $\tan 2\alpha = \frac{3(1 - r\sqrt{5})}{\sqrt{11}(s + \sqrt{5})}, r, s \in \mathbb{N}$, then $r+s$ is equal to ________.

  3. The number of elements in the set $\{x \in [0, 180^\circ] : \tan(x + 100^\circ) = \tan(x + 50^\circ) \tan x \tan(x - 50^\circ)\}$ is _______.
  4. Considering the principal values of inverse trigonometric functions, the value of the expression $\tan\left(2\sin^{-1}\left(\frac{2}{\sqrt{13}}\right) - 2\cos^{-1}\left(\frac{3}{\sqrt{10}}\right)\right)$ is equal to :

  5. Number of solutions of $\sqrt{3}\cos 2\theta + 8\cos \theta + 3\sqrt{3} = 0, \theta \in [-3\pi, 2\pi]$ is :
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