Home
Class 12
MATHS
Let f(x)={{:((alphacotx)/(x)+(beta)/(x^(...

Let `f(x)={{:((alphacotx)/(x)+(beta)/(x^(2))",",0ltxle1),((1)/(3)",",x=0):}`
If f(x) is continuous at x =0, then the value of `alpha^(2)+beta^(2)` is

A

1

B

2

C

5

D

9

Text Solution

Verified by Experts

The correct Answer is:
B

`underset(xrarr0)(lim)f(x)=(1)/(3)`
`rArr" "underset(xrarr0)(lim)(x.alphacotx+beta)/(x^(2))=(1)/(3)`
`rArr" "underset(xrarr0)(lim)(xalpha+betatanx)/(x^(2).tanx)=(1)/(3)`
`rArr" "underset(xrarr0)(lim)(alphax+beta(x+(x^(3))/(3)+...oo))/(x^(3)((tanx)/(x)))=(1)/(3)`
`rArr" "underset(xrarr0)(lim)((alpha+beta)x+((beta)/(3))x^(3)+...oo)/(x^(3))=(1)/(3)`
So, `" "alpha+beta=0`
Also,`" "beta=1rArr alpha=-1`
Promotional Banner

Topper's Solved these Questions

  • CONTINUITY AND DIFFERENTIABILITY

    CENGAGE|Exercise Multiple Correct Answer Type|9 Videos
  • CONTINUITY AND DIFFERENTIABILITY

    CENGAGE|Exercise Comprehension Type|2 Videos
  • CONIC SECTIONS

    CENGAGE|Exercise Solved Examples And Exercises|91 Videos
  • COORDINATE SYSTEM

    CENGAGE|Exercise Multiple Correct Answers Type|2 Videos

Similar Questions

Explore conceptually related problems

Let f(x)={((alpha cotx)/x+beta/x^2,0<|x|lt=1),(1/3,x=0)) If f(x) is continuous at x=0 then the value of alpha^2+beta^2 is 1 b. 2 c. 5 d. 9

Let f(x)={{:(3x-4,0lexle2),(2x+1,2ltxle9):} If f is continuous at x = 2, then what is the value of l ?

f(x)=(1-cos alpha x)/(x sin x), for x!=0,(1)/(2), for x=0 If f is continuous at x=0, then

If f(x) (2^(x)-1)/(1-3^(x)) , x != 0 is continuous at x = 0 then : f(0) =

Let f : R rarr R be defined as f(x) = {{:((x^(3))/((1-cos 2x)^(2)) log_(e)((1+2x e^(-2x))/((1-x e^(-x))^(2))),",",x ne 0),(alpha,",", x =0):} . If f is continuous at x = 0, then alpha is equal to :

If alpha, beta are roots of x^(2)-2x-1=0 , then value of 5alpha^(4)+12beta^(3) is

The function f(x)=((3^(x)-1)^(2))/(sin x*ln(1+x)),x!=0, is continuous at x=0, Then the value of f(0) is

If {:(f(x),=x^(2)+alpha,",","for"x ge 0),(,=2sqrt(x^(2)+1)+beta, ",","for"x lt 0):} is continuous at x = 0 and f((1)/(2))=2 then alpha^(2)+beta^(2) is

If f(x)={{:(x^(2)+alpha," for "xge0),(2sqrt(x^(2)+1)+beta," for "xlt0):} is continuous at x=0 and f((1)/(2))=2 , then alpha^(2)+beta^(2) is

CENGAGE-CONTINUITY AND DIFFERENTIABILITY-Question Bank
  1. Let f(x)={{:((alphacotx)/(x)+(beta)/(x^(2))",",0ltxle1),((1)/(3)",",x=...

    Text Solution

    |

  2. Let f(x) = {(x^(2)-a, if x lt 3),(bsqrt(x-2)+a, if 3 le x lt 6),(2x+b,...

    Text Solution

    |

  3. Given f(x) = {(x^(2)-5x+alpha, -ooltxle 0),(|7-3x|+sin [x], o lt x lt ...

    Text Solution

    |

  4. Let f(x) = {(sqrt(x^(2)-1), x le sqrt10),((sqrt(10x)-7), sqrt10lt xlt...

    Text Solution

    |

  5. Let f(x) = sqrt(x^(2)+px+1)/(x^(2)-p). If f(x) is discontinuous at exa...

    Text Solution

    |

  6. Number of points of non-derivability of the function f(x) = root (3)((...

    Text Solution

    |

  7. If f(x) = {(lim(x rarr oo)(6^(t)+10^(t))^(1/t), x = 0),(x^(2)+4x+C, x ...

    Text Solution

    |

  8. Number of point(s) in [1,2] where f(x) = (-2)^([x^(3)]) is non-differe...

    Text Solution

    |

  9. Consider the function f(x) = {(a^(2)+e^(x), -oo lt x lt 0),(x+2, 0le x...

    Text Solution

    |

  10. Let f(x) = [(sqrt(1+sin^(2)(x^(2))-cos^(3)(x^(2)))/(x^(3)tanx), if x n...

    Text Solution

    |

  11. Let f(x) = {(cos(x^(3)), -ooltxlt0),(sin(x^(3))-|x^(3)-1|, 0lexltoo):}...

    Text Solution

    |

  12. The sum of all values of x for which the function f(x) = sqrt(|x^(2)-5...

    Text Solution

    |

  13. Let f(x) = [(-1, -3 le x lt 0),(x-1, 0le xle 3):} and g(x) = f(|x|)+|f...

    Text Solution

    |

  14. Let f(x) be a differentiable function satisfying f((x+2y)/3)= (f(x)+2f...

    Text Solution

    |

  15. Let f(x) = {((sin alphax^(2))/x^(2), x ne 0),(3/4+1/(4alpha), x = 0):}...

    Text Solution

    |

  16. Let f(x) = {(a tan^(-1)(1/(x-4)), 0 lexlt4),(pi/2, x= 4),(btan^(-1)(2/...

    Text Solution

    |

  17. Let f(x) = {((1+ax)^(1/x), x lt 0),((root(3)(x+c)-1)/(sqrt(x+1)-1), x ...

    Text Solution

    |

  18. The number of points in (-5,5) where f(x)=[x](x^(3)-x)^(2)) is non-dif...

    Text Solution

    |

  19. If f(x) = cos (x (cos)1/x) and g(x) = (In(sec^(2)x))/(x sin x) are bot...

    Text Solution

    |

  20. Consider , f(x) = {(|(x-x^(3) 1 2),(0 2 3x^(4)),(x^(2) 4x x^(3)-3x^(5)...

    Text Solution

    |

  21. Number of points where f(x)= max {2-|x|, min {x^(2)-1}} is not differe...

    Text Solution

    |