# Recently Active Trignometry Questions

• Q1 If roots of x3-px2-r=0 are tanÎ±,tanÎ²,tanÎ³ ,find value of sec2Î±.sec2Î².sec2Î³ I did by converting secx into tanx and then using equation to solve ......any better method ?? Q2 Prove that sinx/cos3x + sin3x/cos9x + sin9x ...
replied2010-02-19 02:25:50
• \sum_{r=0}^{9}{\left(-1 \right)^r\cos^{10}\frac{r\pi}{10}} any short solution using complex? ...
• If x, y \varepsilon ( 0, \pi ) and (sin 3 x + sin 4 y) + 3 cosec x + 4 cosec y - 9 =0, then no. of solutions of the equation sin x sin y = 1/2 in ( 0, \pi ) is A) 0 B) 1 C) 2 D) infinite ...
replied2010-02-17 19:50:45
• Number of solutions of the equation \mid x-1\mid + \mid x\mid + \mid x+1\mid = \mid sinx\mid + \mid cosx\mid is, A) 1 B) 0 C) 2 D) 4 ...
replied2010-02-17 08:25:15
• \\\texttt{Given\; that\;} \\H_k=\frac{k(k-1)}{2}cos\left ( \frac{k(k-1)\pi}{2} \right )\\\texttt{Find \;teh\; value}\; of\\\;H_{19}+H_{20}+H_{21}......H_{98} try it..for practice ...
replied2010-02-16 07:09:38
• ses x - cos x = K1 cosec x- sin x = k2 the eliminant of x between the equation is a) ( K22*K1)2/3 + (K2*K12)2/3 =1 b) K22 + K12/K22 = 2 c) K12/3*K22/3(k12/3 + K22/3) = 1 d) K1*K22 + k2*K12 = 2 ...
replied2010-02-15 05:13:29
• Find the length of internal angle bisector CF. A) 2ab/a+b cos (C/2) B) a+b/2ab cos (C/2) C) sin (C/2) D) none of these. Plzz post the solution too.. ...
replied2010-02-12 23:40:35
• find the angles and the side lengths of the pedal triangle of triangle ABC ....a ,b ,c as usual side lengths of triangle ABC with angle A B and C **EDITED** LEAVE IT I GOT IT ...
• In a triangle ABC, cos2A+cos2B+cos2C=1. Then the triangle is a)right angled b) obtuse angled c)acute angled d)equilateral ...
replied2010-02-12 08:02:05
• Number of solution(s) of the equation cos^{-1}(e^{x}) + sin^{-1}(kx^{2}-2)=\frac{\pi }{2},k>0, is A)0 B) 1 C) 2 D) infinite ...
replied2010-02-10 23:41:02
• If A>0 , B>0 and A+B=âˆ©/3 , then the maximum value of tan A tan B is a) 1/6 b)1/3 c)1/2 d)1 ans b) .............solve it ...
replied2010-02-10 22:07:00
• The set of values possible of Î¸ in [-Î ,Î ], such that 1-sin Î¸ / 1+sin Î¸ is equal to sec Î¸- tan Î¸ is a)[0,Î /2] b)[0,Î /2)Ï…(Î /2,Î ] c)[-Î ,0] d)(-Î /2, Î /2) ans d ...
replied2010-02-10 08:35:01
• If cos4Î¸.sec2Î±, 1/2 and sin4Î¸.cosec2Î± are in AP, then cosec8Î¸sec6Î± , 1/2, sin8Î¸.cosec6Î± are in a)AP b)GP c)HP d)none ans a) ...
• tan2 (pi/7) + tan2 (2pi/7) + tan2 (3pi/7) ...
replied2010-02-09 06:19:21
• Q1. 18tan^{16}\frac{\pi }{18} - 816tan^{14}\frac{\pi }{18} + ... - 816tan^{2}\frac{\pi }{18} = _____ Q2. If ABC is a triangle and cot(A/2), cot(B/2), cot(C/2) are in GP, then minimum value of cot(B/2) is _________ Q3. Prove t ...
replied2010-02-04 20:24:08
• please prove these identities : $\sin (\frac{\pi}{2m})\sin (\frac{2\pi}{2m})\sin (\frac{3\pi}{2m})\dots\sin (\frac{(m-1)\pi}{2m}) =\frac{\sqrt{m}}{2^{m-1}}$ \sin (\frac{\pi}{4m})\sin (\frac{3\pi}{4m})\sin (\frac{5\pi}{4m})\ ...
• *Image* This question can be solved by using AM>=GM. i JUST WANT TO KNOW THAT IN WHICH TYPE OF QUESTIONS SHOULD WE USE THIS CONCEPT? ...
replied2010-01-26 09:25:52
• Number os solutions of the eqn tan x+ sec x= 2cos x , lying in the interval [0,2âˆ©) is a) 0 b)1 c)2 d)3 ...
replied2010-01-24 18:14:24
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replied2010-01-23 22:03:21
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replied2010-01-23 21:38:43
• The least value of 9tan2âˆ‚ +4cot2âˆ‚ is a) 13 b)5 c) 0 d) none of these ans. d ...
replied2010-01-23 21:37:17
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replied2010-01-23 21:35:22
• For all values of x and y, sec2t = 4xy/(x+y)2 will be true if and only if a) x+y \neq 0 b) x=y , x \neq 0 c) x=y d) x \neq 0, y \neq 0 Ans b ...
replied2010-01-23 06:27:35
• find value of sin^{-1}(sin(2010))= ...
replied2010-01-22 07:23:01
• 1.find min value of:secA+secB+secC where A+B+C=PI. ...
replied2010-01-22 00:44:52
• let teh 3 sides of a triangle be integers l,m,n respect...satisfying l>m>n and \left\{\frac{3^{l}}{10^{4}} \right\}= \left\{\frac{3^{m}}{10^{4}} \right\}= \left\{\frac{3^{n}}{10^{4}} \right\} wer {x} is fractional part ...
replied2010-01-15 21:26:45
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replied2010-01-12 06:49:51
• evaluate- cot^{2}\left(\frac{\pi }{11} \right)+cot^{2}\left(\frac{2\pi }{11} \right)+cot^{2}\left(\frac{3\pi }{11} \right)+cot^{2}\left(\frac{4\pi }{11} \right)+cot^{2}\left(\frac{5\pi }{11} \right) ...
replied2010-01-09 03:07:47
• Q1 If tan-14=4tan-1x then x5-7x3+5x2+2x+9870 is equal to ? ...
replied2010-01-08 00:55:55
• 2\sqrt{2}sin10[\frac{sec5}{2}+\frac{cos40}{sin5}-2sin35] calculate without using trigo tables ...
replied2010-01-08 00:05:30