English

If Tan−1 3 + Tan−1 X = Tan−1 8, Then X = (A) 5 (B) 1/5 (C) 5/14 (D) 14/5 - Mathematics

Advertisements
Advertisements

Question

If tan−1 3 + tan−1 x = tan−1 8, then x =

Options

  • 5

  • 1/5

  • 5/14

  • 14/5

MCQ
Advertisements

Solution

(b) `1/5`

We know that 
\[\tan^{- 1} x + \tan^{- 1} y = \tan^{- 1} \frac{x + y}{1 - xy}\]
Now,
\[\tan^{- 1} 3 + \tan^{- 1} x = \tan^{- 1} 8\]
\[ \Rightarrow \tan^{- 1} \left( \frac{3 + x}{1 - 3x} \right) = \tan^{- 1} 8\]
\[ \Rightarrow \frac{3 + x}{1 - 3x} = 8\]
\[ \Rightarrow 3 + x = 8 - 24x\]
\[ \Rightarrow 3 - 8 = - 24x - x\]
\[ \Rightarrow - 5 = - 25x\]
\[ \Rightarrow x = \frac{5}{25} = \frac{1}{5}\]
\[\]

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Inverse Trigonometric Functions - Exercise 4.16 [Page 121]

APPEARS IN

RD Sharma Mathematics [English] Class 12
Chapter 4 Inverse Trigonometric Functions
Exercise 4.16 | Q 18 | Page 121

RELATED QUESTIONS

Write the value of `tan(2tan^(-1)(1/5))`


​Find the principal values of the following:

`cos^-1(-1/sqrt2)`


`sin^-1(sin2)`


Evaluate the following:

`cos^-1{cos  (5pi)/4}`


Evaluate the following:

`cos^-1(cos5)`


Evaluate the following:

`tan^-1(tan4)`


Evaluate the following:

`sec^-1(sec  (5pi)/4)`


Evaluate the following:

`cosec^-1(cosec  (6pi)/5)`


Evaluate the following:

`cot^-1(cot  (19pi)/6)`


Write the following in the simplest form:

`tan^-1{(sqrt(1+x^2)-1)/x},x !=0`


Write the following in the simplest form:

`sin^-1{(x+sqrt(1-x^2))/sqrt2},-1<x<1`


Write the following in the simplest form:

`sin^-1{(sqrt(1+x)+sqrt(1-x))/2},0<x<1`


Evaluate the following:

`sin(cos^-1  5/13)`


Evaluate the following:

`sin(tan^-1  24/7)`


Evaluate the following:

`sin(sec^-1  17/8)`


Evaluate the following:

`sec(sin^-1  12/13)`


Evaluate the following:

`cot(cos^-1  3/5)`


Evaluate:

`sin(tan^-1x+tan^-1  1/x)` for x > 0


If `cot(cos^-1  3/5+sin^-1x)=0`, find the values of x.


`tan^-1x+2cot^-1x=(2x)/3`


Prove the following result:

`tan^-1  1/4+tan^-1  2/9=sin^-1  1/sqrt5`


Evaluate the following:

`sin(1/2cos^-1  4/5)`


`tan^-1  2/3=1/2tan^-1  12/5`


`4tan^-1  1/5-tan^-1  1/239=pi/4`


Solve the following equation for x:

`tan^-1((2x)/(1-x^2))+cot^-1((1-x^2)/(2x))=(2pi)/3,x>0`


For any a, b, x, y > 0, prove that:

`2/3tan^-1((3ab^2-a^3)/(b^3-3a^2b))+2/3tan^-1((3xy^2-x^3)/(y^3-3x^2y))=tan^-1  (2alphabeta)/(alpha^2-beta^2)`

`where  alpha =-ax+by, beta=bx+ay`


If `sin^-1x+sin^-1y+sin^-1z=(3pi)/2,`  then write the value of x + y + z.


What is the value of cos−1 `(cos  (2x)/3)+sin^-1(sin  (2x)/3)?`


Write the value of tan1\[\left\{ \tan\left( \frac{15\pi}{4} \right) \right\}\]


If 4 sin−1 x + cos−1 x = π, then what is the value of x?


If \[\cos\left( \tan^{- 1} x + \cot^{- 1} \sqrt{3} \right) = 0\] , find the value of x.

 

If \[\tan^{- 1} \left( \frac{\sqrt{1 + x^2} - \sqrt{1 - x^2}}{\sqrt{1 + x^2} + \sqrt{1 - x^2}} \right)\]  = α, then x2 =




The value of tan \[\left\{ \cos^{- 1} \frac{1}{5\sqrt{2}} - \sin^{- 1} \frac{4}{\sqrt{17}} \right\}\] is

 


The number of real solutions of the equation \[\sqrt{1 + \cos 2x} = \sqrt{2} \sin^{- 1} (\sin x), - \pi \leq x \leq \pi\]


If \[\cos^{- 1} \frac{x}{2} + \cos^{- 1} \frac{y}{3} = \theta,\]  then 9x2 − 12xy cos θ + 4y2 is equal to


If \[\sin^{- 1} \left( \frac{2a}{1 - a^2} \right) + \cos^{- 1} \left( \frac{1 - a^2}{1 + a^2} \right) = \tan^{- 1} \left( \frac{2x}{1 - x^2} \right),\text{ where }a, x \in \left( 0, 1 \right)\] , then, the value of x is

 


Find the domain of `sec^(-1) x-tan^(-1)x`


Find the value of x, if tan `[sec^(-1) (1/x) ] = sin ( tan^(-1) 2) , x > 0 `.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×