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Verified AnswerIf tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=?Tan x + tan 2x + tan 3x - tan x tan 2x tan 3x = 0 tan x + tan 2x + tan 3x ( 1 - tan x tan 2x ) = 0 tan x + tan 2x = - tan 3x ( 1 - tan x tan 2x ) ( tan x + tan 2x )/ ( 1 - tan x tan 2x ) = - tan 3x tan 3x = - tan 3x 2 tan 3x = 0 tan 3x = 0 3x = 2kpi where k = 0, 1,2,3,4,5,... x = 2 k pi/3 where k = 0 , 1, 2 ,3 , 4 , 5 , 6.
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This question is part of UPSC exam. View all Class 11 coursesMost Upvoted AnswerIf tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=?Solution:To solve the given equation, we will use the trigonometric identity:tan A tan B = tan (A + B) - tan (A - B)Let's rewrite the given equation using this identity:tan x tan 2x tan 7x = tan x tan 2x tan 7xNow, we can apply the identity to both sides of the equation:tan (x + 2x) - tan (x - 2x) = tan (x + 2x) - tan (x - 2x)Simplifying the equation further:tan 3x - tan (-x) = tan 3x - tan (-x)Since tan (-x) = -tan x, we can rewrite the equation as:tan 3x + tan x = tan 3x + tan xNow, let's combine like terms on both sides of the equation:2tan 3x = 2tan 3xDividing both sides of the equation by 2, we get:tan 3x = tan 3xThis equation holds true for all values of x. Therefore, there are infinitely many solutions for x.Explanation:The given trigonometric equation, tan x tan 2x tan 7x = tan x tan 2x tan 7x, can be simplified using the trigonometric identity tan A tan B = tan (A + B) - tan (A - B). By applying this identity, we obtain the equation tan 3x - tan (-x) = tan 3x - tan (-x). Since tan (-x) = -tan x, we can rewrite the equation as tan 3x + tan x = tan 3x + tan x. By combining like terms on both sides, we arrive at the equation 2tan 3x = 2tan 3x. Dividing both sides by 2, we get tan 3x = tan 3x. This equation holds true for all values of x, which means there are infinitely many solutions for x.Answered by Prof. Tarun Kaushik ·
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Question Description If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=? for Class 11 2026 is part of Class 11 preparation. The Question and answers have been prepared according to the Class 11 exam syllabus. Information about If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=? covers all topics & solutions for Class 11 2026 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=?.Solutions for If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=? in English & in Hindi are available as part of our courses for Class 11. Download more important topics, notes, lectures and mock test series for Class 11 Exam by signing up for free.Here you can find the meaning of If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=? defined & explained in the simplest way possible. Besides giving the explanation of If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=?, a detailed solution for If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=? has been provided alongside types of If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=? theory, EduRev gives you an ample number of questions to practice If tan x tan 2x tan 7x = tan x+ tan 2x+ tan 7x, then x=? tests, examples and also practice Class 11 tests.
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