Home
Class 12
MATHS
The function f(x)=-x//2+sinx defined on ...

The function `f(x)=-x//2+sinx` defined on `[-pi//3,\ pi//3]` is (a) increasing (b) decreasing (c) constant (d) none of these

Text Solution

Verified by Experts

`f(x)=frac{-x}{2}+sin x` defined on `[frac{-pi}{3}, frac{pi}{3}] `
` therefore f^{prime}(x)=frac{-1}{2}+cos x `
` Rightarrow f^{prime}(x) ge 0 forall x in[frac{-pi}{3}, frac{pi}{3}] `
` {[because text { for } x in[frac{-pi}{3}, frac{pi}{3}], cos x ge frac{1}{2}]}`
Therefore , the given function is increasing .
Promotional Banner

Topper's Solved these Questions

  • HIGHER ORDER DERIVATIVES

    RD SHARMA|Exercise Solved Examples And Exercises|176 Videos
  • INDEFINITE INTEGRALS

    RD SHARMA|Exercise Solved Examples And Exercises|1401 Videos

Similar Questions

Explore conceptually related problems

The function f(x)=-(x)/(2)+sin x defined on [-(pi)/(3),(pi)/(3)] is

In the interval (1,2), function f(x)=2|x-1|+3|x-2| is (a) increasing (b) decreasing (c) constant (d) none of these

If g(x)=f((|x|)/(x)) is a a an increasing function b)a decreasing function c)a constant function d) none of these

Let f(x)=tan^(-1)(g(x)) , where g(x) is monotonically increasing for 0

The value of c in Lagranges theorem for the function f(x)=log sin x in the interval [(pi)/(6),(5 pi)/(6)] is (pi)/(4) (b) (pi)/(2)(2 pi)/(3) (d) none of these

The function f(x)=(x)/(1+|x|) is (a) strictly increasing (b) strictly decreasing (c) neither increasing nor decreasing (d) none of these

Prove that the function f(x)=tan x-4x is strictly decreasing on (-pi/3,pi/3)

Show that the function given by f (x) = sinx is (a) strictly increasing in (0,pi/2) (b) strictly decreasing in (pi/2,pi) (c) neither increasing nor decreasing in (0, pi)

Find the intervals in which the function given by f(x)=sin3x, x in [0, (pi)/(2)] is : (a) increasing (b) decreasing.

Show that the function f(x)=sin(2x+pi/4) is decreasing on (3 pi/8,5 pi/8)

RD SHARMA-INCREASING AND DECREASING FUNCTION -Solved Examples And Exercises
  1. The function f(x)=x^2\ e^(-x) is monotonic increasing when (a) x in R...

    Text Solution

    |

  2. Function f(x)=cosx-2\ lambda\ x is monotonic decreasing when (a) lambd...

    Text Solution

    |

  3. In the interval (1,\ 2) , function f(x)=2|x-1|+3|x-2| is (a) monotonic...

    Text Solution

    |

  4. Function f(x)=x^3-27 x+5 is monotonically increasing when (a) x<-3 (b...

    Text Solution

    |

  5. Function f(x)=2x^3-9x^2+12 x+29 is monotonically decreasing when (a) x...

    Text Solution

    |

  6. If f(x)=k x^3-9x^2+9x+3 monotonically increasing in R , then k<3 (b) ...

    Text Solution

    |

  7. f(x)=2x-tan^(-1)x-log{x+sqrt(x^2+1)} is monotonically increasing when ...

    Text Solution

    |

  8. Function f(x)=|x|-|x-1| is monotonically increasing when (a) x<0 (b) ...

    Text Solution

    |

  9. Every invertible function is (a) monotonic function          (b) co...

    Text Solution

    |

  10. In the interval (1,\ 2) , function f(x)=2|x-1|+3|x-2| is (a) increasin...

    Text Solution

    |

  11. If the function f(x)=cos|x|-2a x+b increases along the entire number s...

    Text Solution

    |

  12. The function f(x)=x/(1+|x|) is (a) strictly increasing (b) strictly...

    Text Solution

    |

  13. The function f(x)=(lambdasinx+2cosx)/(sinx+cosx) is increasing, if (a)...

    Text Solution

    |

  14. Function f(x)=a^x is increasing on R , if (a) a >0 (b) a<0 (c) 0 lt ...

    Text Solution

    |

  15. Function f(x)=(log)a x is increasing on R , if (a) 0<a<1 (b) a >1 (c...

    Text Solution

    |

  16. Let varphi(x)=f(x)+f(2a-x) and f"(x)>0 for all x in [0,\ a] . Then, va...

    Text Solution

    |

  17. If the function f(x)=x^2-k x+5 is increasing on [2,\ 4] , then (a) k i...

    Text Solution

    |

  18. The function f(x)=-x//2+sinx defined on [-pi//3,\ pi//3] is (a) increa...

    Text Solution

    |

  19. If the function f(x)=x^3-9k\ x^2+27 x+30 is increasing on R , then (a)...

    Text Solution

    |

  20. The function f(x)=x^9+3x^7+64 is increasing on (a) R (b) (-oo,\ 0) (...

    Text Solution

    |