Home
Class 11
MATHS
If sec x =- (13)/(12) and (pi)/(2) lt x ...

If `sec x =- (13)/(12)` and `(pi)/(2) lt x lt pi ,` find the value of `sin 2x`

A

`(60)/(169)`

B

`(-60)/(169)`

C

`(120)/(169)`

D

`(-120)/(169)`

Text Solution

Verified by Experts

The correct Answer is:
D

Since x lies in Quadrant II , we have sin `x gt 0` cos x ` lt 0` and tan `x lt 0`
Now sec `x =(-13)/(12) rArr " cos " x = (1)/(" sec x ") =(-12)/(13)`
`:. " sin " x = + sqrt(1- "cos"^(2) ) x =+ sqrt(1- (144)/(169)) = + sqrt((25)/(169)) =(5)/(13)`
And tan `x= (sin x)/(cos x) =(5)/(13) xx ((-13)/(13)) =((-13)/(12)) = (-5)/(12)`
`(i) " sin " 2x = 2 " sin x cos x "`
`={2xx (5)/(13) xx ((-12))/(13)}= (-120)/(169)`
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC , OR CIRCULAR, FUNCTIONS

    RS AGGARWAL|Exercise Exercise (15A)|10 Videos
  • TRIGONOMETRIC , OR CIRCULAR, FUNCTIONS

    RS AGGARWAL|Exercise Exercise (15B)|20 Videos
  • THREE-DIMENSIONAL GEOMETRY

    RS AGGARWAL|Exercise EXERCISE 26 C|13 Videos
  • TRIGONOMETRIC EQUATIONS

    RS AGGARWAL|Exercise EXERCISE|21 Videos

Similar Questions

Explore conceptually related problems

If tan x=(-5)/(12) " and " (pi)/(2) lt x lt pi find the value of cos 2x

if cos x= (-sqrt(15))/(4) " and " (pi)/(2) lt x lt pi find the value of sin x .

If tan x=(-3)/(4) " and" (3pi)/(2) lt x lt 2 pi find the value of "(i) " sin 2x , "(ii) " cos 2x , "(iii) " tan 2x

If cos x=(-3)/(5) " and " .(pi)/(2) lt x lt pi find the values of (i) " sin .(x)/(2) " " (ii) " cos " (x)/(2) " " (iii) " tan " (x)/(2)

If tan x = -(4)/(3), (pi)/(2) lt x lt pi , then find the value of sin(x/2), cos(x/2) and tan(x/2) .

If tan x=(-4)/(3) " and " .(pi)/(2) lt x lt pi find the values of (i) " sin ".(x)/(2) " ""(ii) cos " .(x)/(2) " ""(iii) tan ".(x)/(2)

If " sin " x =- (1)/(2) " and " pi lt x lt .(3pi)/(2) find the value of (i) " sin "2x , (ii) " cos " 2x (iii) " tan " 2x

If sin x=(sqrt(5))/(3) "and " .(pi)/(3) lt x lt pi find the values of (i) " sin " (x)/(2) " " (ii) " cos " (x)/(2) " " (iii) " tan " (x)/(2)

If cos x=(-3)/(5) " and " pi lt x lt .(3pi)/(2) find the value of (i) "sin 2x "" ""(ii) cos 2x "" ""(iii) tan 2x "

If tanx=-(4)/(3), (3pi)/(2) lt x lt 2pi , find the value of 9sec^(2)x-4 cot x .