Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NDA 2015
Exam
NDA
Year
2015
Subject
Mathematics
Chapter
Trigonometric Ratios & Identities

NDA 2015 · Mathematics · Trigonometric Ratios & Identities

If p= (-(11 π)/(6)), q= ((21 π)/(4))and r= ((283 π)/(6)), then...

If p=tan⁡(−11π6),q=tan⁡(21π4)andr=cot⁡(283π6),\mathrm{p}=\tan \left(-\frac{11 \pi}{6}\right), \mathrm{q}=\tan \left(\frac{21 \pi}{4}\right)and \mathrm{r}=\cot\left(\frac{283 \pi}{6}\right), then which of the following is/are correct? 1. The value of p×r\mathrm{p} \times \mathrm{r} is 2. 2. p,qp, q and rr are in G.P. Select the correct answer using the code given below :

Options

  1. A1 only
  2. B2 only
  3. CBoth 1 and 2
  4. DNeither 1 nor 2

Correct answer

B. 2 only

Step-by-step solution

p=tan⁡(−11π6)p=−tan⁡(2π−π6)p=tan⁡π6=13q=tan⁡(21π4)=tan⁡(6π−3π4)q=−tan⁡3π4=+tan⁡π4=1r=cot⁡(283π6)=cot⁡(46π+7π6)=cot⁡(π+π6)r=cot⁡π6=3p×r=13×3=1\begin{aligned} & \mathrm{p}=\tan \left(-\frac{11 \pi}{6}\right) \\ & \mathrm{p}=-\tan \left(2 \pi-\frac{\pi}{6}\right) \\ & \mathrm{p}=\tan \frac{\pi}{6}=\frac{1}{\sqrt{3}} \\ & \mathrm{q}=\tan \left(\frac{21 \pi}{4}\right) \\ &=\tan \left(6 \pi-\frac{3 \pi}{4}\right) \\ & \mathrm{q}=-\tan \frac{3 \pi}{4}=+\tan \frac{\pi}{4}=1 \\ & \mathrm{r}=\cot \left(\frac{283 \pi}{6}\right) \\ &=\cot \left(46 \pi+\frac{7 \pi}{6}\right)=\cot \left(\pi+\frac{\pi}{6}\right) \\ & \mathrm{r}=\cot \frac{\pi}{6}=\sqrt{3} \\ & \mathrm{p} \times \mathrm{r}=\frac{1}{\sqrt{3}} \times \sqrt{3}=1 \end{aligned}\thereforeStatement(1)isincorrect.alsoStatement (1) is incorrect. also\frac{\mathrm{p}}{\mathrm{q}}=\frac{\mathrm{q}}{\mathrm{r}}=\frac{1}{\sqrt{3}}Sop,Sop,q, rareinG.P.are in G.P.\therefore$ Statement (2) is correct.
Practice Trigonometric Ratios & Identities on Quantrex Academy →

More from Trigonometric Ratios & Identities

If θ lies in the fourth quadrant and 3 θ+4=0 , then what is the value of 2θ+ 2θ ? NDA 2026If α+ β=0= α+ β , α≠β then what is a value of 2α+ 2β+2 (α+β) ? NDA 2026If 2 4β= 2α+ 2α , then which one of the following is a possible value of (α+β) ? NDA 2026If x= θ- θ and y= θ+ θ , then which one of the following is correct ? NDA 2026If θ=(1)/(3) , then what is the value of ((θ)/(2)) ((3θ)/(2)) ? NDA 2026If A and B are acute angles such that 2A+2B=π , then what is the maximum value of A· B ? NDA 2026x+ 3 x is maximum when x is equal to NDA 2026In a triangle ABC , A= B+ C then what is ((B)/(2))+ ((B)/(2))equal to ? NDA 2026If α and β are complementary angles such that α-β=(π)/(6) and m β=n α , then what is… NDA 2026For the following two (02) items: Let A + B = p and A + B = q . What is (p^2 - q^2)/(p^2… NDA 2025For the following two (02) items: Let p = cosec\, 20° and q = cosec\, 70° . What is (p^2… NDA 2025For the following two (02) items: Let A + B = p and A + B = q . What is (p)/(q) equal to? NDA 2025For the following two (02) items: Let p = cosec\, 20° and q = cosec\, 70° . What is ( 3… NDA 2025Consider the following for the three (03) items that follow: Let p = 35° , q = 25° and r… NDA 2025Consider the following for the three (03) items that follow: Let p = 35° , q = 25° and r… NDA 2025Consider the following for the three (03) items that follow: Let p = 35° , q = 25° and r… NDA 2025 Full Trigonometric Ratios & Identities list Trigonometric Ratios & Identities JEE Maths PYQsJEE Mathematics PYQs All NDA PYQs