Home
Class 12
MATHS
If x ,\ y ,\ z in [-1,1] such that cos^(...

If `x ,\ y ,\ z in [-1,1]` such that `cos^(-1)x+cos^(-1)y+cos^(-1)z=0` , find `x+y+z` .

A

`-3`

B

3

C

0

D

`3 pi`

Text Solution

Verified by Experts

The correct Answer is:
B

We have
`x,y,z in[-1,1]`
`rarr -1lexle1-1leyle1,-1lezle1`
`rarr 0lecos^(-1)xlepi0lecos^(-1)ylepi,0lecos^(-1)zlepi`
`therefore cos^(-1)x+cos^(-1)y+cos^(-1)z=0`
`rarr cos^(-1)x=0, cos^(-1)y=0 and cos^(-1)z=0`
`rarr x=y=z=3`
Hence x+y+z=3
Promotional Banner

Topper's Solved these Questions

  • INVERSE TRIGONOMETRIC FUNCTIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Section I - Solved Mcqs|71 Videos
  • INVERSE TRIGONOMETRIC FUNCTIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Section II - Assertion Reason Type|11 Videos
  • INDEFINITE INTEGRALS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|30 Videos
  • LIMITS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|58 Videos

Similar Questions

Explore conceptually related problems

If x , y ,z in [-1,1] such that cos^(-1)x+cos^1y+cos^(-1)z=3pi, then find the values of (1). x y+y z+z y and (2). x(y+z)+y(z+x)+z(x+y)

If x , y ,z in [-1,1] such that cos^(-1)x+cos^1y+cos^(-1)z=3pi, then find the values of (1) x y+y z+z y and (2) x(y+z)+y(z+x)+z(x+y)

If x , y ,z in [-1,1] such that cos^(-1)x+cos^1y+cos^(-1)z=3pi, then find the values of (1) x y+y z+z x and (2) x(y+z)+y(z+x)+z(x+y)

If x , y , z in [-1,1] such that sin^(-1)x+sin^(-1)y+sin^(-1)z=-(3pi)/2, find the value of x^2+y^2+z^2dot

If x , y , z in [-1,1] such that sin^(-1)x+sin^(-1)y+sin^(-1)z=-(3pi)/2, find the value of x^2+y^2+z^2dot

If cos^(-1)x+cos^(-1)y+cos^(-1)z=pi , prove that x^2+y^2+z^2+2x y z=1.

If cos^(-1)x+cos^(-1)y+cos^(-1)z=pi , prove that x^2+y^2+z^2+2x y z=1.

If cos^(-1)x + cos^(-1)y + cos^(-1)z = pi, then xy + yz +zx is equal to

If cos^(-1)x + cos^(-1)y + cos^(-1)z = 3pi, then xy + yz +zx is equal to

Given that cos(x-y) +cos (y-z) +cos (z-x)=-3/5 find cos x+ cos y + cos z

OBJECTIVE RD SHARMA ENGLISH-INVERSE TRIGONOMETRIC FUNCTIONS -Chapter Test
  1. If x ,\ y ,\ z in [-1,1] such that cos^(-1)x+cos^(-1)y+cos^(-1)z=0 , f...

    Text Solution

    |

  2. Solve sin^(-1)(1-x)-2sin ^(-1)x=pi/2

    Text Solution

    |

  3. If (tan^(-1)x)^2+(cot^(-1)x)^2=(5pi^2)/8, then find xdot

    Text Solution

    |

  4. If tantheta + tan(theta + pi/3) + tan(theta-pi/3)= Ktan3theta, then K ...

    Text Solution

    |

  5. If -1 le x le -1/2, then sin^(-1)(3x-4x^3) equals

    Text Solution

    |

  6. The numerical value of "tan"(2tan^(-1)(1/5)-pi/4 is equal to

    Text Solution

    |

  7. If tan(x+y)=33, and x= tan^(-1)3, then: y=

    Text Solution

    |

  8. Two angles of a triangle are cot^-1 2 and cot^-1 3, then the third ang...

    Text Solution

    |

  9. The greater of the two angles A=2tan^(-1)(2sqrt(2)-1) and B=3sin^(-1)(...

    Text Solution

    |

  10. Let a, b and c be positive real numbers. Then prove that tan^(-1) sqrt...

    Text Solution

    |

  11. If sin^(-1)x+sin^(-1)y+sin^(-1)z=(3pi)/(2) the value of x^(100)+y^(10...

    Text Solution

    |

  12. The value of (alpha^(3))/(2) cosec^(2) ((1)/(2) tan^(-1) ((alpha)/(bet...

    Text Solution

    |

  13. If a,b are positive quantitis and if a(1)=(a+b)/(2), b(1)=sqrt(a(1)b) ...

    Text Solution

    |

  14. tan""(2pi)/(5)-tan""(pi)/(15)-sqrt3tan""(2pi)/(5)tan""(pi)/(15) is equ...

    Text Solution

    |

  15. If a(1), a(2), a(3),...., a(n) is an A.P. with common difference d, th...

    Text Solution

    |

  16. If x=sin(2tan^(- 1)2), y=sin(1/2tan^(- 1)(4/3)) , then -

    Text Solution

    |

  17. Which of the following angles is greater? theta1=sin^(-1)+sin^(-1)1/3o...

    Text Solution

    |

  18. The value of cos[1/2 cos^(-1){cos(sin^(-1)((sqrt63)/(8)))}] is

    Text Solution

    |

  19. Solve for x: - tan^(-1)("x"+1)+tan^(-1)("x"-1)=tan^(-1) (8/31)

    Text Solution

    |

  20. If alpha = sin^(-1)(sqrt(3)/2)+sin^(-1)(1/3) , beta =cos ^(-1)(sqrt(3)...

    Text Solution

    |

  21. The sum of the two angles cot^(-1) 3 and cosec^(-1) sqrt(5) is

    Text Solution

    |