मराठी

Show that 2tan-1{tan α2⋅tan(π4-β2)}=tan-1 sinαcosβcosα+sinβ - Mathematics

Advertisements
Advertisements

प्रश्न

Show that `2tan^-1 {tan  alpha/2 * tan(pi/4 - beta/2)} = tan^-1  (sin alpha cos beta)/(cosalpha + sinbeta)`

बेरीज
Advertisements

उत्तर

L.H.S. = `tan^-1  (2tan  alpha/2 * tan (pi/4 - beta/2))/(1 - tan^2  alpha/2 tan^2 (pi/4 - beta/2))`  ......`("since"  2 tan^-1x = tan^-1  (2x)/(1 - x^2))`

= `tan^-1  (2tan  alpha/2  (1 - tan  beta/2)/(1 + tan  beta/2))/(1 - tan^2  alpha/2  ((1 - tan  beta/2)/(1 + tan  beta/2))^2)`

= `tan^-1  (2tan  alpha/2 (1 - tan^2  beta/2))/((1 + tan  beta/2)^2 - tan^2  alpha/2 (1 - tan  beta/2)^2)`

= `tan^-1  (2tan  alpha/2 (1 - tan^2  beta/2))/((1 + tan^2  beta/2)(1 - tan^2  alpha/2) + 2   beta/2 (1 + tan^2  alpha/2))`

= `tan^-1  ((2tan  alpha/2)/(1 + tan^2  alpha/2) - (1 - tan^2  beta/2)/(1 + tan^2  beta/2))/((1 - tan^2  alpha/2)/(1 + tan^2  alpha/2) + (2tan  beta/2)/(1 + tan^ beta/2))`

= `tan^-1  ((sin alpha cos beta)/(cos alpha + sin beta))`

= R.H.S.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 2: Inverse Trigonometric Functions - Solved Examples [पृष्ठ २७]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 2 Inverse Trigonometric Functions
Solved Examples | Q 20 | पृष्ठ २७

संबंधित प्रश्‍न

 

If `sin (sin^(−1)(1/5)+cos^(−1) x)=1`, then find the value of x.

 

Write the following function in the simplest form:

`tan^(-1)  x/(sqrt(a^2 - x^2))`, |x| < a


Find the value of the following:

`tan^-1 [2 cos (2  sin^-1  1/2)]`


if `tan^(-1)  (x-1)/(x - 2) + tan^(-1)  (x + 1)/(x + 2) = pi/4` then find the value of x.


Find the value of the given expression.

`tan(sin^(-1)  3/5 + cot^(-1)  3/2)`


Prove that:

`tan^(-1)  63/16 = sin^(-1)  5/13 + cos^(-1)  3/5`


Solve  `tan^(-1) -  tan^(-1)  (x - y)/(x+y)` is equal to

(A) `pi/2`

(B). `pi/3` 

(C) `pi/4` 

(D) `(-3pi)/4`


Solve for x : `tan^-1 ((2-"x")/(2+"x")) = (1)/(2)tan^-1  ("x")/(2), "x">0.`


Find the number of solutions of the equation `tan^-1 (x - 1) + tan^-1x + tan^-1(x + 1) = tan^-1(3x)`


Choose the correct alternative:

If `sin^-1x + sin^-1y = (2pi)/3` ; then `cos^-1x + cos^-1y` is equal to


Choose the correct alternative:

`tan^-1 (1/4) + tan^-1 (2/9)` is equal to


Choose the correct alternative:

sin(tan–1x), |x| < 1 is equal to


Evaluate tan (tan–1(– 4)).


Evaluate: `tan^-1 sqrt(3) - sec^-1(-2)`.


Evaluate: `sin^-1 [cos(sin^-1 sqrt(3)/2)]`


If `tan^-1x = pi/10` for some x ∈ R, then the value of cot–1x is ______.


Evaluate `cos[cos^-1 ((-sqrt(3))/2) + pi/6]`


Prove that `sin^-1  8/17 + sin^-1  3/5 = sin^-1  7/85`


The value of cot–1(–x) for all x ∈ R in terms of cot–1x is ______.


If `"cot"^-1 (sqrt"cos" alpha) - "tan"^-1 (sqrt"cos" alpha) = "x",` the sinx is equal to ____________.


`"cot" ("cosec"^-1  5/3 + "tan"^-1  2/3) =` ____________.


`"tan"^-1 1/3 + "tan"^-1 1/5 + "tan"^-1 1/7 = "tan"^-1 1/8 =` ____________.


Simplest form of `tan^-1 ((sqrt(1 + cos "x") + sqrt(1 - cos "x"))/(sqrt(1 + cos "x") - sqrt(1 - cos "x")))`, `π < "x" < (3π)/2` is:


The value of `"tan"^-1 (3/4) + "tan"^-1 (1/7)` is ____________.


`"cos"^-1["cos"(2"cot"^-1(sqrt2 - 1))]` = ____________.


The value of `"cos"^-1 ("cos" ((33pi)/5))` is ____________.


`"sin"^-1 (1 - "x") - 2  "sin"^-1 "x" = pi/2`


`"cos"^-1 1/2 + 2  "sin"^-1 1/2` is equal to ____________.


If `"sin"^-1 (1 - "x") - 2  "sin"^-1 ("x") = pi/2,` then x is equal to ____________.


The Government of India is planning to fix a hoarding board at the face of a building on the road of a busy market for awareness on COVID-19 protocol. Ram, Robert and Rahim are the three engineers who are working on this project. “A” is considered to be a person viewing the hoarding board 20 metres away from the building, standing at the edge of a pathway nearby. Ram, Robert and Rahim suggested to the firm to place the hoarding board at three different locations namely C, D and E. “C” is at the height of 10 metres from the ground level. For viewer A, the angle of elevation of “D” is double the angle of elevation of “C” The angle of elevation of “E” is triple the angle of elevation of “C” for the same viewer. Look at the figure given and based on the above information answer the following:

Measure of ∠EAB = ________.


`tan^-1  1/2 + tan^-1  2/11` is equal to


What is the simplest form of `tan^-1  sqrt(1 - x^2 - 1)/x, x ≠ 0`


`sin^-1(1 - x) - 2sin^-1 x = pi/2`, tan 'x' is equal to


The set of all values of k for which (tan–1 x)3 + (cot–1 x)3 = kπ3, x ∈ R, is the internal ______.


Find the value of `tan^-1 [2 cos (2 sin^-1  1/2)] + tan^-1 1`.


If `tan^-1 ((x - 1)/(x + 1)) + tan^-1 ((2x - 1)/(2x + 1)) = tan^-1 (23/36)` = then prove that 24x2 – 23x – 12 = 0


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×