Home
Class 12
MATHS
The sum of all the solutions of cottheta...

The sum of all the solutions of `cottheta=sin2theta(theta!=npi, n in t ege r)` , `0lt=thetalt=pi,` is `(3pi)/2` (b) `pi` (c) 3`pi/4` (d) `2pi`

A

`3pi//2`

B

`pi`

C

`3pi//4`

D

`2pi`

Text Solution

Verified by Experts

The correct Answer is:
A

From the given relation
`cos theta=(2 sin theta cos theta) sin theta, sin theta ne 0`
`rArr sin theta= pm 1/sqrt(2) or cos theta =0`
`rArr theta= pi/4, (3pi)/4, pi/2" "( :' theta in [0, pi])`
Then the sum of roots is `3pi//2`.
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC EQUATIONS

    CENGAGE|Exercise Exercise (Multiple)|31 Videos
  • TRIGONOMETRIC EQUATIONS

    CENGAGE|Exercise Exercise (Comprehension)|20 Videos
  • TRIGONOMETRIC EQUATIONS

    CENGAGE|Exercise Exercise 4.9|6 Videos
  • TRIGNOMETRIC RATIOS IDENTITIES AND TRIGNOMETRIC EQUATIONS

    CENGAGE|Exercise Question Bank|34 Videos
  • TRIGONOMETRIC FUNCTIONS

    CENGAGE|Exercise SINGLE CORRECT ANSWER TYPE|38 Videos

Similar Questions

Explore conceptually related problems

The sum of all the solutions of cot theta=sin2 theta(theta!=n pi,n integer) 0<=theta<=pi, is (a) (3 pi)/(2) (b) pi (c) 3(pi)/(4) (d) 2 pi

Find the sum of all the solution of the equation cos theta-sin3 theta=cos2 theta in[0,2 pi]

The sum of all the solution of the equation cos theta cos((pi)/(3)+theta)cos((pi)/(3)-theta)=(1)/(4)theta in[0,6 pi] (A) 15 pi(B)30 pi(C)(100 pi)/(3) (D) none of these

If 3 sin 2 theta = 2 sin 3 theta and 0 lt theta lt pi , then sin theta =

If theta=sin^(-1){sin(-600o)} , then one of the possible values of theta is pi/3 (b) pi/2 (c) (2pi)/3 (d) (-2pi)/3

The period of cos5 theta is (a) pi^(2) (b) 2 pi (c) 2 pi/5 (d) pi/3

If (1-tantheta)/(1+tantheta) = 1/sqrt3 , where theta in (0, pi/2) , then theta = (a) pi/6 (b) pi/4 (c) pi/12 (d) pi/3

The general solution of the equation 7cos^(2)theta+3sin^(2)theta=4 is theta=2n pi+-(pi)/(6),nZ b.theta=2n pi+-(2 pi)/(3),nZ c.theta=2n pi+-(pi)/(3),nZ d.none of these

A general solution of tan^(2)theta+cos2 theta=1 is (n in Z)n pi=(pi)/(4) (b) 2n pi+(pi)/(4)n pi+(pi)/(4) (d) n pi

CENGAGE-TRIGONOMETRIC EQUATIONS-Exercise (Single)
  1. If x, y in [0, 2pi] and sin x + sin y=2, then the value of x+y is

    Text Solution

    |

  2. Number of roots of cos^2x+(sqrt(3)+1)/2sinx-(sqrt(3))/4-1=0 which lie ...

    Text Solution

    |

  3. The sum of all the solutions of cottheta=sin2theta(theta!=npi, n in t ...

    Text Solution

    |

  4. The number of solutions of 12 cos^(3) x-7 cos^(2) x+4 cos x=9 is

    Text Solution

    |

  5. Number of solutions of the equation sin x + cos x-2sqrt(2) sin x cos x...

    Text Solution

    |

  6. The general solution of (tan 5x-tan 4x)/(1+ tan 5 x tan 4x)=1 is

    Text Solution

    |

  7. If xsina+ysin2a+zsin3a=sin4a xsinb+ysin2b+zsin3b=sin4b xsinc+ysin2c+...

    Text Solution

    |

  8. The number of solutions of the equation sin 2 theta-2 cos theta +4 sin...

    Text Solution

    |

  9. The number of distinct real roots of the equation tan(2pix)/(x^2+x+1)=...

    Text Solution

    |

  10. The smallest positive value of x (in radians) satisfying the equation ...

    Text Solution

    |

  11. The number of solution of sin^(4)x-cos^(2) x sin x+2 sin^(2)x+sin x=0 ...

    Text Solution

    |

  12. The range of 'y, such that the equation in x, y + cos x = sin x has a ...

    Text Solution

    |

  13. Solution of the equation sin (sqrt(1+sin 2 theta))= sin theta + cos th...

    Text Solution

    |

  14. One of the general solutions of sqrt(3) cos theta -3 sin theta =4 sin ...

    Text Solution

    |

  15. The general solution of the equation 8 cos x cos 2x cos 4x = sin 6x//s...

    Text Solution

    |

  16. (sin^(3) theta-cos^(3) theta)/(sin theta - cos theta)- (cos theta)/sqr...

    Text Solution

    |

  17. For 0<x , y<pi, the number of ordered pairs (x , y) satisfying the sys...

    Text Solution

    |

  18. The least positive solution of cot (pi/(3 sqrt(3)) sin 2x)=sqrt(3) lie...

    Text Solution

    |

  19. The number of real roots of the equation cosec theta + sec theta-sqrt(...

    Text Solution

    |

  20. If =lt=xlt=2pi, then the number of solutions of 3(sinx+cosx)-(sin^3x+c...

    Text Solution

    |