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If p=tan(-(11pi)/(6)).q=tan((21pi)/(4)) ...

If p=`tan(-(11pi)/(6)).q=tan((21pi)/(4))` and r=cot`((383pi)/(6))`, then which of the following is/are correct?
1.The value of `pxxr` is 2
2.p.q and r are in G.P
Select the correct answer using the code given below:

A

Only 1

B

Only 2

C

Both 1 and 2

D

Neither 1 nor 2

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the values of \( p \), \( q \), and \( r \) based on the given expressions and check the conditions provided in the question. ### Step 1: Calculate \( p = \tan\left(-\frac{11\pi}{6}\right) \) Using the property of tangent, we have: \[ \tan(-\theta) = -\tan(\theta) \] Thus, \[ p = \tan\left(-\frac{11\pi}{6}\right) = -\tan\left(\frac{11\pi}{6}\right) \] Next, we can express \( \frac{11\pi}{6} \) in terms of a reference angle: \[ \frac{11\pi}{6} = 2\pi - \frac{\pi}{6} \] Since \( \frac{11\pi}{6} \) is in the fourth quadrant, where tangent is negative: \[ \tan\left(\frac{11\pi}{6}\right) = -\tan\left(\frac{\pi}{6}\right) = -\frac{1}{\sqrt{3}} \] Therefore, \[ p = -\left(-\frac{1}{\sqrt{3}}\right) = \frac{1}{\sqrt{3}} \] ### Step 2: Calculate \( q = \tan\left(\frac{21\pi}{4}\right) \) First, simplify \( \frac{21\pi}{4} \): \[ \frac{21\pi}{4} = 5\pi + \frac{\pi}{4} = 2\pi + 3\pi + \frac{\pi}{4} \] Since \( \tan \) has a period of \( \pi \): \[ \tan\left(\frac{21\pi}{4}\right) = \tan\left(\frac{\pi}{4}\right) = 1 \] Thus, \[ q = 1 \] ### Step 3: Calculate \( r = \cot\left(\frac{383\pi}{6}\right) \) First, simplify \( \frac{383\pi}{6} \): \[ \frac{383\pi}{6} = 63\pi + \frac{5\pi}{6} \quad (\text{since } 63 = 10 \times 6 + 3) \] Using the periodicity of \( \cot \): \[ \cot\left(\frac{383\pi}{6}\right) = \cot\left(\frac{5\pi}{6}\right) \] In the second quadrant, where cotangent is negative: \[ \cot\left(\frac{5\pi}{6}\right) = -\cot\left(\frac{\pi}{6}\right) = -\sqrt{3} \] Thus, \[ r = -\sqrt{3} \] ### Step 4: Check the conditions 1. **Calculate \( p \times r \)**: \[ p \times r = \left(\frac{1}{\sqrt{3}}\right) \times (-\sqrt{3}) = -1 \] Since \( -1 \neq 2 \), the first statement is **false**. 2. **Check if \( p, q, r \) are in Geometric Progression (G.P.)**: For \( p, q, r \) to be in G.P., the condition \( q^2 = p \cdot r \) must hold: \[ q^2 = 1^2 = 1 \] Calculate \( p \cdot r \): \[ p \cdot r = \left(\frac{1}{\sqrt{3}}\right) \cdot (-\sqrt{3}) = -1 \] Since \( 1 \neq -1 \), they are **not** in G.P. Thus, the second statement is also **false**. ### Final Answer Both statements are false.
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