Home
Class 11
MATHS
(a)Derive geometrically that cos(x+y)=co...

(a)Derive geometrically that `cos(x+y)=cos x cos y-sin x sin y`.Hence deduce the valueof `cos 75^@`

Promotional Banner

Topper's Solved these Questions

  • SOLVED PAPER 2018-1

    OSWAAL PUBLICATION|Exercise EXERCISE|58 Videos

  • SOLVED PAPER 2019-1

    OSWAAL PUBLICATION|Exercise EXERCISE|54 Videos

Similar Questions

Explore conceptually related problems

Prove geometrically that cos (x+y) =cosx cosy +sin x sin y

Prove geometrically that cos(x + y) = cos x cos y - sinx sin y and hence prove cos((pi)/(2) + x) = - sin x .

Prove Geometrically cos(x+y)=cosx,cosy-sinx.siny and hence prove that cos(x-y)= cosxcosy+sinxsiny using unit circle concept ?

To cos(A+B)=cosx.cosy - sin x sin "and hence find "cos75^(@)

If sin x+sin y=3(cos y-cos x) then the value of sin 3 x+sin 3 y=

If y = cos(log sin x), then dy/dx =

The maximum value of y=a cos x + b sin x is

OSWAAL PUBLICATION-SOLVED PAPER 2018-2-EXERCISE
  1. A bag contains 9 discs of which 4 are red 3 are blue and 2 are yellow....

    Text Solution

    |

  2. A die is thrown. Find the probability that (i) A prime number will a...

    Text Solution

    |

  3. A die is thrown.Write the sample space.Also find the probability of th...

    Text Solution

    |

  4. A die is thrown, find the probability of following events: (i) A pri...

    Text Solution

    |

  5. Define a modulus function . Draw its graph. Also write down its domai...

    Text Solution

    |

  6. ((sin 7x + sin 5x ) +(sin 9x + sin 3x))/( (cos 7x + cos 5x ) + (cos 9x...

    Text Solution

    |

  7. 1^(2)+2^(2)+3^(2)+............+n^(2)=(n(n+1)(2n+1))/6 forall n in N.

    Text Solution

    |

  8. Solve the following system of inequalities graphically x+2yle8,2x+yle8...

    Text Solution

    |

  9. What is the number of ways of choosing 4 cards from a pack of 52 play...

    Text Solution

    |

  10. What is the number of ways of choosing 4 cards from a pack of 52 play...

    Text Solution

    |

  11. What is the number of ways of choosing 4 cards from a pack of 52 cards...

    Text Solution

    |

  12. What is the number of ways of choosing 4 cards from a pack of 52 play...

    Text Solution

    |

  13. State and prove Bionomial theorem for any positive integer n.

    Text Solution

    |

  14. Derive the expression for the length of the perpendicular drawn from t...

    Text Solution

    |

  15. Prove that underset(xrarr0)lim(sinx/x=1) ?

    Text Solution

    |

  16. Find the mean deviation about median for the following data:

    Text Solution

    |

  17. (a)Derive geometrically that cos(x+y)=cos x cos y-sin x sin y.Hence de...

    Text Solution

    |

  18. (b) Find the sum to n terms of the series 1 xx 2 xx 3 + 2 xx 3 xx 4 + ...

    Text Solution

    |

  19. Find the equation of hyperbola in the form (x^2)/(a^2)-(y^2)/(b^2)=1, ...

    Text Solution

    |

  20. Find the derivative of f(x)(x + cos x)/(tan x) w.r. to x . . .

    Text Solution

    |