Home
Class 12
MATHS
sin4theta can be written as...

`sin4theta` can be written as

A

`4sintheta(1-2sin^(2)theta)sqrt(1-sin^(2)theta)`

B

`2sinthetacosthetasin^(2)theta`

C

`4sintheta-6sin^(3)theta`

D

None of the above

Text Solution

AI Generated Solution

The correct Answer is:
To express \( \sin 4\theta \) in terms of \( \sin \theta \), we can follow these steps: ### Step 1: Use the double angle formula for sine We start with the identity for \( \sin 4\theta \): \[ \sin 4\theta = \sin(2 \cdot 2\theta) = 2 \sin 2\theta \cos 2\theta \] ### Step 2: Substitute \( \sin 2\theta \) Next, we apply the double angle formula for \( \sin 2\theta \): \[ \sin 2\theta = 2 \sin \theta \cos \theta \] Substituting this into our expression gives: \[ \sin 4\theta = 2(2 \sin \theta \cos \theta) \cos 2\theta = 4 \sin \theta \cos \theta \cos 2\theta \] ### Step 3: Substitute \( \cos 2\theta \) Now, we use the double angle formula for cosine: \[ \cos 2\theta = 1 - 2 \sin^2 \theta \] Substituting this into our expression results in: \[ \sin 4\theta = 4 \sin \theta \cos \theta (1 - 2 \sin^2 \theta) \] ### Step 4: Express \( \cos \theta \) We can express \( \cos \theta \) in terms of \( \sin \theta \) using the Pythagorean identity: \[ \cos \theta = \sqrt{1 - \sin^2 \theta} \] Substituting this into our expression gives: \[ \sin 4\theta = 4 \sin \theta \sqrt{1 - \sin^2 \theta} (1 - 2 \sin^2 \theta) \] ### Final Expression Thus, we can write: \[ \sin 4\theta = 4 \sin \theta (1 - 2 \sin^2 \theta) \sqrt{1 - \sin^2 \theta} \]

To express \( \sin 4\theta \) in terms of \( \sin \theta \), we can follow these steps: ### Step 1: Use the double angle formula for sine We start with the identity for \( \sin 4\theta \): \[ \sin 4\theta = \sin(2 \cdot 2\theta) = 2 \sin 2\theta \cos 2\theta \] ...
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC FUNCTIONS OF COMPOUND ANGLES

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise Exercise 2 (MISCELLANEOUS PROBLEMS)|20 Videos
  • TRIGONOMETRIC FUNCTIONS

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise EXERCISE 2 (MISCELLANEOUS PROBLEMS)|26 Videos
  • VECTORS

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise ( MHT CET Corner)|66 Videos

Similar Questions

Explore conceptually related problems

sin4 theta can be written as (a) 4sin theta(1-2sin^(2)theta)sqrt(1-sin^(2)theta)(b)2sin theta cos theta sin^(2)theta(c)4sin theta-6sin^(3)theta(d) None of the above

Show that cos theta((1)/(1-sin theta)-(1)/(1+sin theta)) can be written in the form k tan theta and find the value of ^( k.)

If cos7theta=costheta-sin4theta , then the general value of theta is

If (sin theta+cos theta)/(sin theta-cos theta)=3 then sin^4 theta-cos^4 theta=

sin4 theta.sin6 theta=

If sin theta=4 cos theta , then what is the value of sin theta cos theta ? यदि sin theta=4 cos theta , है, तो sin theta cos theta का मान क्या होगा ?

If 8 sin theta=4+cos theta then sin theta=

If sin theta+cos theta=a, then sin^(4)theta+cos^(4)theta=

MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS-TRIGONOMETRIC FUNCTIONS OF COMPOUND ANGLES-Exercise 2 (MISCELLANEOUS PROBLEMS)
  1. If sinA+sinB=C,cosA+cosB=D, then the value of sin(A+B)=

    Text Solution

    |

  2. If theta lies in the first quardrant and costheta=(8)/( 17 ), then fi...

    Text Solution

    |

  3. If tanx+tan((pi)/(3)-x)+tan((2pi)/(3)+x)=3, then

    Text Solution

    |

  4. If sin(theta+alpha)=a andsin(theta+beta)=b, then prove that cos(alpha...

    Text Solution

    |

  5. The expression cos^(2)(A-B)+cos^(2)B-2cos(A-B)cosAcosB is

    Text Solution

    |

  6. If tanalpha,tanbeta are the roots of the equation x^(2)+px+q=0(pne0), ...

    Text Solution

    |

  7. If cos(A-B)=3/5 and tanA .tan B=2, then

    Text Solution

    |

  8. tan100^0+tan125^0+tan100^0tan125^0 is equal to

    Text Solution

    |

  9. If pi/2 lt alpha lt pi, pi lt beta lt 3pi/2; sin alpha = 15/17 and tan...

    Text Solution

    |

  10. If sintheta=(12)/(13),(0ltthetalt(pi)/(2))and cosphi=-(3)/(5),(piltph...

    Text Solution

    |

  11. If tanA-tan B=x, and cot B-cotA=y, then find the value of cot(A-B).

    Text Solution

    |

  12. sin4theta can be written as

    Text Solution

    |

  13. If cos 2B =cos(A+C)/cos( A-C), then tanA, tanB, tanC are in

    Text Solution

    |

  14. If (2sinalpha)/({1+cosalpha+sinalpha})=y, then ({1-cosalpha+sinalph...

    Text Solution

    |

  15. (sintheta+sin2theta)/(1+costheta+cos2theta)=

    Text Solution

    |

  16. (sin3theta-cos3theta)/(sintheta+costheta)+1=

    Text Solution

    |

  17. If tanalpha=(1)/(7) and tanbeta=(1)/(3), then cos2alpha is equal to

    Text Solution

    |

  18. If tanbeta=costhetatanalpha, then "tan"^(2)(theta)/(2)=

    Text Solution

    |

  19. sec^2 A(1+sec2A) = 2sec2A

    Text Solution

    |

  20. 2sinAcos^3A-2sin^3AcosA=

    Text Solution

    |