Popular Trignometry Questions

Prove it: sin-1(1-x) - 2sin-1x = pi/2 ...

i have some unsolved questions in inverse trigno..........posting here....... Q1 Find range of values of a if sum of series \sum_{n=1}^{infinity}{(\frac{sec^{-1}\sqrt{\left|x \right|}+cosec^{-1}\sqrt{\left|x \right|}}{\pi a}} ...

given S = tan-1(1/3)+tan-1(1/5)+tan-1(1/7)+..........+tan-1(1/(2n-1)) if S = Î /4 find n ...

cos-1(x2-1 / x2+1) + 1/2 * tan-1(2x/1-x2) = 2Ï€/3. Solve for x ...

WELL THIS MIGHT SEEM ILLOGOCAL TO FEW PEOPLE BUT I KNOW THAT MOST OF THEM DONNO THIS. BUT VERY USEFUL IN SOME PROBLEMS. in a triangle ABC, angle bisector of A, AD is drawn. what is lengthof AD? {of course in terms of a,b,c ,A ...

Sum of roots of sin^{-1}\frac{ax}{c}+sin^{-1}\frac{bx}{c}=sin^{-1}x is ????? ...

solve one by one. not randomly... please. 1]the total 8 digit numbers of the form x_{1}x_{2}x_{3}x_{4}x_{5}x_{6}x_{7}x_{8} such that x5 is the greatest digit and digits towards the left and right of x5 are in decreasing order ...

Sn=cos1+cos2+cos3+cos4+....+cosn Find \lim_{n\rightarrow \infty}\frac{S_{n}}{n} ...

This is a repost. The last time I posted this one it got buried somewhere Find \sum_{r=1}^n \tan ^{-1} \frac{2r}{2r^4+1} ...

if A=B=pi/2 what is tan (A+B)=-infinity(formulae) it should be zero why ...

IF (sin4x)/2+(cos4x)/3=1/5 then (a)tan2x=2/3 (b)sin8x/8+cos8x/27=1/125 (c)tan2x=1/3 (d)sin8x/8+cos8x/27=2/125??? It's mulit ans question... ...

If A,B,C are acute positive angles such that A+B+C=Πand cot A cot B cot C=k,then a) k≤1/3√3 b) k≥1/3√3 c) k<1/9 d) k>1/3 The ans is a..... but please can ny 1 giv a proper method 4 dis.... ...

If sinx+tanx=5/6 find sinx*tanx. By converting everything to sinx we get a quartic equation but how to solve that? ...

2 sin x= mod x + a find a such that there is no real root ...

Sides a,b,c of a triangle ABC are in AP \cos(\theta_1)=\frac{a}{b+c} , \cos(\theta_2)=\frac{b}{a+c} and \cos(\theta_3)=\frac{c}{a+b} Then \tan^2\left(\frac{\theta_1}{2} \right)+\tan^2\left(\frac{\theta_3}{2} \right) =? ...

Prove that \sqrt [44] {\tan 1^{\circ} \tan 2^{\circ}...\tan 44^{\circ}} < \sqrt 2 -1 <\frac{\tan 1^{\circ} + \tan 2^{\circ}+...+\tan 44^{\circ}}{44} ...

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 ...

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 ...

ABC is an equilateral triangle. P is any point in it satisfying PA=3, PB=4 & PC=5 units. Find area of the triangle. ...

sin x + cos x = 1/2 x ε 0, π find tan x ...

sinA sinB sin C + cos A cos B=1 then the value of sin C=? ...

try to prove the following inequality given that a,b,c are positive reals Cyclic[(a^2) / {b(a + 2b)}] >= 1 a harddddddddddddddddd problem not at all easy unless u guys know Cauchy Schwarz inequality ...

1..IF P,Q,R MAY BE PERIMETER ,CIRCUMRADIUS AND INRADIUS OF AN ARBITARY TRIANGLE THE WHICH OF THE FOLLOWING MAY NOT BE ALWAYS TRUE-- (A)P>Q+R (B) P≤Q+R (C)P/6<Q+R<6P (MULTI ANSWER) ...

show that the equation secθ + cosecθ = c has two solutions between 0 and 2π if c2 < 8 and four solutions if c2 > 8. I've tried but didn't get the correct answer. ...

1) If sin x + sin y = 3(cos y - cos x), then find the value of sin3x + sin3y ? 2) If sin (x/2) + cos (x/2) = -1/2 , 3pie/2 < x < 2pie, then the value of sin2x? ...

wen appylying formulae lyk tan inv + tan invers = tan -1(x+y/1-xy) can sum1 tell me if ther is a genreal rule for addtn/subtctn of Î wen negative n all dat........ OR IT HAS TO BE REMEMBERED CASE to CASE basiss?? ...

Evaluate: \sin \left(\frac{\pi}{14} \right)\sin \left(\frac{3\pi}{14} \right)\sin \left(\frac{5\pi}{14} \right)\sin \left(\frac{7\pi}{14} \right)\sin \left(\frac{9\pi}{14} \right)\sin \left(\frac{13\pi}{14} \right) .sin(11pi/ ...

Consider the set of points (x,y) in the plane which satisfied x2+y2<=100 and sin(x+y)>=0. solve the following ques. 1.) the region given by sin(x+y)>=o will be a) angular region between two concentric ci ...

Find the sum of all x in [0, 2Ï€] which satisfy the equation 3 cot2 x + 8 cot x + 3 = 0 ...

Prove: \prod_{k=1}^{n}{\left[ 1+2\cos\frac{2\pi.3^k}{3^n+1}\right]}=1 Source: Titu Andreescu's Book.. ...