Home
Class 11
MATHS
The number of values of yin[-2pi,2pi] sa...

The number of values of `yin[-2pi,2pi]` satisfying the equation `|sin2x|+|cos2x|=|siny|` is 3 (b) 4 (c) 5 (d) 6

Text Solution

Verified by Experts

`|sin2x| +|cos2x| = |siny|`
`=>(|sin2x| +|cos2x|)^2 = (|siny|)^2`
`=>sin^2 2x+cos^2 2x +2|sin2xcos2x| = sin^2y`
`=>1+|sin4x| = sin^2y`
`=>1-sin^2y = -|sin4x|`
`=>cos^2y = -|sin4x|`
Now, `cos^2y` will always be positive and `-|sin4x|` will always be negative.
So, only possible value that will satisfy the equation will be when both sides are `0`.
...
Promotional Banner

Topper's Solved these Questions

  • STRAIGHT LINES

    CENGAGE PUBLICATION|Exercise All Questions|486 Videos

Similar Questions

Explore conceptually related problems

The number of values of x in the interval [0,5pi] satisfying the equation 3 sin^2 x-7 sin x+2=0 is :

The number of value of 'x' in the interval [0 , 3pi] satisfying the equation 2 sin^2 x + 5 sin x - 3 = 0 is

The number of values of x in [0 , 4pi] satisfying abs(sqrt3 cos x - sin x) ge 2 , is

The values of x_1 between 0 and 2pi , satisfying the equation cos3x+cos2x=sin(3x)/2+sinx/2 are

Number of solution(s) satisfying the equation 1/(sinx)-1/(sin2x)=2/(sin4x) in [0,4pi] equals 0 (b) 2 (c) 4 (d) 6

Find the values of x in (-pi,pi) which satisfy the equation 8^(1+|cosx|+|cos^2x|+|cos^3x|+...))=4^3

The number of solution of the equation |2sinx-sqrt(3)|^(2cos^(2)x-3cosx+1)=1in[0,pi] is (a) 2 (b) 3 (c) 4 (d) 5

The sum of all the solution in [0,4pi] of the equation tanx+cotx+1=cos(x+pi/4)i s (a) 3pi (b) pi/2 (c) (7pi)/2 (d) 4pi

The number of solution (s) of the equation sin^4 x + cos^4 x = sinx cosx in [0 , 2pi]

The number of solutions of the equation cos6x+tan^2x+cos(6x)tan^2x=1 in the interval [0,2pi] is (a) 4 (b) 5 (c) 6 (d) 7

CENGAGE PUBLICATION-TRIGONOMETRIC FUNCTIONS-All Questions
  1. Each question has four choices a,b,c and d out of which only one is...

    Text Solution

    |

  2. In triangle ABC, prove that sin(B+C-A)+sin(C+A-B)+sin(A+B-C) =4sin A...

    Text Solution

    |

  3. The number of values of yin[-2pi,2pi] satisfying the equation |sin2x|+...

    Text Solution

    |

  4. If alpha+beta =(pi/2) and beta+gamma=alpha, then the tanalpha equals:

    Text Solution

    |

  5. prove that a^2sin2B+b^2sin2A=4Delta

    Text Solution

    |

  6. The equation cos^8x+bcos^4x+1=0 will have a solution if b belongs to

    Text Solution

    |

  7. Let f(n)=2cosn xAAn in N , then f(1)f(n+1)-f(n) is equal to

    Text Solution

    |

  8. If in triangle A B C, \delta = a^2-(b-c)^2 , then find the value of ta...

    Text Solution

    |

  9. The number of solutions of [sinx+cosx]=3+[-sinx]+[-cosx](w h e r e[] d...

    Text Solution

    |

  10. If sintheta1-sintheta2=a a n d costheta1+costheta2=b , then (a)a^2+b...

    Text Solution

    |

  11. If a , ba n dc are the side of a triangle, then the minimum value of (...

    Text Solution

    |

  12. sinx+cosx=y^2-y+a has no value of x for any value of y if a belongs to...

    Text Solution

    |

  13. If (cosx)/a=(cos(x+theta))/b=(cos(x+2theta))/c=(cos(x+3theta))/d then ...

    Text Solution

    |

  14. Let PQR be a triangle of area Delta with a=2,b=7/2 and c=5/2, where a,...

    Text Solution

    |

  15. If the inequality sin^2x+acosx+a^2>1+cosx holds for any x in R , then...

    Text Solution

    |

  16. If cosalpha+cosbeta=0=sinalpha+sinbeta, then cos2alpha+cos2beta is e...

    Text Solution

    |

  17. If the angle A ,Ba n dC of a triangle are in an arithmetic propression...

    Text Solution

    |

  18. The equation sin^4x-2cos^2x+a^2=0 can be solved if

    Text Solution

    |

  19. Value of (3+cot80^0cot20^0)/(cot80^0+cot20^0) is equal to (a)cot20^0...

    Text Solution

    |

  20. Let A B C be a triangle such that /A C B=pi/6 and let a , b and c deno...

    Text Solution

    |