Home
Class 12
MATHS
Let g(x)=((x-1)^(n))/(logcos^(m)(x-1)),0...

Let `g(x)=((x-1)^(n))/(logcos^(m)(x-1)),0ltxlt2` m and n integers, `m ne0, n gt0` and. If `lim_(xrarr1+) g(x)=-1`, then

A

n= 1, m = 1

B

n = 1, m = -1

C

n = 2, m = 2

D

n gt 2, m = n

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the limit of the function \( g(x) = \frac{(x-1)^n}{(\log(\cos(x-1)))^m} \) as \( x \) approaches \( 1 \) from the right. We are given that \( \lim_{x \to 1^+} g(x) = -1 \), and we need to find the values of \( m \) and \( n \) under the conditions \( m \neq 0 \) and \( n > 0 \). ### Step-by-Step Solution: 1. **Substitution**: Let \( h = x - 1 \). As \( x \to 1^+ \), \( h \to 0^+ \). Thus, we can rewrite the limit: \[ \lim_{h \to 0^+} g(1+h) = \lim_{h \to 0^+} \frac{h^n}{(\log(\cos(h)))^m} \] 2. **Analyzing the Logarithm**: We know that as \( h \to 0 \), \( \cos(h) \to 1 \) and \( \log(\cos(h)) \to \log(1) = 0 \). We can use the Taylor series expansion for \( \cos(h) \): \[ \cos(h) \approx 1 - \frac{h^2}{2} \quad \text{for small } h \] Thus, \[ \log(\cos(h)) \approx \log\left(1 - \frac{h^2}{2}\right) \approx -\frac{h^2}{2} \quad \text{(using } \log(1-x) \approx -x \text{ for small } x\text{)} \] 3. **Substituting Back**: Substitute this approximation back into the limit: \[ \lim_{h \to 0^+} \frac{h^n}{\left(-\frac{h^2}{2}\right)^m} = \lim_{h \to 0^+} \frac{h^n}{\left(-\frac{1}{2}\right)^m h^{2m}} = \lim_{h \to 0^+} \frac{2^m h^n}{-h^{2m}} = \lim_{h \to 0^+} -2^m h^{n - 2m} \] 4. **Finding Conditions for the Limit**: For the limit to exist and equal \(-1\), we need: - If \( n - 2m < 0 \), then \( h^{n - 2m} \to 0 \) as \( h \to 0^+ \) (the limit goes to 0). - If \( n - 2m = 0 \), then \( h^{n - 2m} \) approaches a constant, and we can evaluate the limit. - If \( n - 2m > 0 \), then \( h^{n - 2m} \to \infty \) (the limit goes to \(-\infty\)). Therefore, we set: \[ n - 2m = 0 \implies n = 2m \] 5. **Substituting Back to Find Values**: Now substituting \( n = 2m \) into the limit: \[ \lim_{h \to 0^+} -2^m h^{0} = -2^m \] For this limit to equal \(-1\): \[ -2^m = -1 \implies 2^m = 1 \implies m = 0 \quad \text{(which contradicts } m \neq 0\text{)} \] Therefore, we need to find integer values of \( m \) and \( n \) that satisfy \( n = 2m \) and \( m \neq 0 \). 6. **Choosing Values**: The simplest choice is \( m = 1 \) and \( n = 2 \) (since \( n \) must be greater than 0). Thus: \[ m = 1, \quad n = 2 \] ### Final Result: The values of \( m \) and \( n \) are: \[ m = 1, \quad n = 2 \]

To solve the problem, we need to analyze the limit of the function \( g(x) = \frac{(x-1)^n}{(\log(\cos(x-1)))^m} \) as \( x \) approaches \( 1 \) from the right. We are given that \( \lim_{x \to 1^+} g(x) = -1 \), and we need to find the values of \( m \) and \( n \) under the conditions \( m \neq 0 \) and \( n > 0 \). ### Step-by-Step Solution: 1. **Substitution**: Let \( h = x - 1 \). As \( x \to 1^+ \), \( h \to 0^+ \). Thus, we can rewrite the limit: \[ \lim_{h \to 0^+} g(1+h) = \lim_{h \to 0^+} \frac{h^n}{(\log(\cos(h)))^m} ...
Promotional Banner

Topper's Solved these Questions

  • LIMITS

    CENGAGE ENGLISH|Exercise ComprehensionType|2 Videos
  • LIMITS

    CENGAGE ENGLISH|Exercise Multiple Correct Answer Type|2 Videos
  • LIMITS

    CENGAGE ENGLISH|Exercise Archives JEE ADVANCED|2 Videos
  • JEE 2019

    CENGAGE ENGLISH|Exercise Chapter 10|9 Videos
  • LINEAR COMBINATION OF VECTORS, DEPENDENT AND INDEPENDENT VECTORS

    CENGAGE ENGLISH|Exercise DPP 1.2|10 Videos

Similar Questions

Explore conceptually related problems

Let f(x)=x^(m/n) for x in R where m and n are integers , m even and n odd and 0

Prove that lim_(xrarr0) ((1+x)^(n) - 1)/(x) = n .

Evaluate : lim_(xrarr0)((1-x)^(n)-1)/(x)

Let f(x)=(x+x^2+...+x^n-n)/(x-1), g(x)=(4^n+5^n)^(1/n) and alpha and beta are the roots of equation lim_(x rarr 1) f(x)= lim_(n rarr oo) g(x) then the value of sum_(n=0)^oo (1/alpha+1/beta)^n is

If f(x) =[m x^2+n , x 1 . For what integers m and n does both (lim)_(x->1)f(x)dot

The value of lim_(xrarr oo) 1+(1)/(x^n)^x,ngt 0 , is

If f(x)=lim_(nrarroo) (cos(x)/(sqrtn))^(n) , then the value of lim_(xrarr0) (f(x)-1)/(x) is

lim_(xrarr1)(x^(m)-1)/(x^(n)-1) is equal to

If f(x)={((sqrt(g(x))-1)/(sqrtx-1)"," , x ne 1),(1",",x=1):} and g'(1)=2, g(1)=1, then lim_(xrarr1)f(x) is equal to

lim_(xrarr0)((1+x)^(n)-1)/(x) is equal to

CENGAGE ENGLISH-LIMITS-Single Correct Answer Type
  1. If agt0, b gt0 than lim(nrarroo) ((a-1+b^((1)/(n)))/(a))^(n)=

    Text Solution

    |

  2. If f(x)=lim(nrarroo) (cos(x)/(sqrtn))^(n), then the value of lim(xrarr...

    Text Solution

    |

  3. lim(xrarr0) (log(e^(x^(2))+2sqrtx))/(tansqrtx) is equal to

    Text Solution

    |

  4. Let f:RrarrR be such that f(a)=1, f(a)=2. Then lim(x to 0)((f^(2)(a+x)...

    Text Solution

    |

  5. The value of (lim)(nvecoo)((sqrt(n^2+n)-1)/n)^2sqrt(n^(2+n)-1) is e b....

    Text Solution

    |

  6. If f(n)=underset(xto0)lim{(1+"sin"(x)/(2))(1+"sin"(x)/(2^(2)))...(1+"s...

    Text Solution

    |

  7. lim(nrarroo) (1-x+x.root n e)^(n) is equal to

    Text Solution

    |

  8. The value of lim(xrarr1) (root(13)x-root7x)/(root5x-root3x) is

    Text Solution

    |

  9. The value of underset(xrarr1)(lim)(root(13)x-root7x)/(root5x-root3x) i...

    Text Solution

    |

  10. The value of lim(x rarr 0) (1-cos2x)/(e^(x^(2))-e^(x)+x) is

    Text Solution

    |

  11. If f^(prime)(a)=1/4, t h e n(lim)(hvec0)(f(a+2h^2)-f(a-2h^2))/(f(a+h^3...

    Text Solution

    |

  12. (lim)(xvec0^+)1/(xsqrt(x))("a t a n"^(-1)(sqrt(x))/a-btan^(-1)(sqrt(x)...

    Text Solution

    |

  13. The value of lim(x->0)((1+2x)/(1+3x))^(1/x^2)e^(1/x) is e^(5/2) b. e^2...

    Text Solution

    |

  14. Let f : R rarr R be a differentiable function at x = 0 satisfying f(0)...

    Text Solution

    |

  15. The value of lim(xrarr(3pi)/(4)) (1+root3(tanx))/(1-2cos^(2)x) is

    Text Solution

    |

  16. Let g(x)=((x-1)^(n))/(logcos^(m)(x-1)),0ltxlt2 m and n integers, m ne0...

    Text Solution

    |

  17. Number of integral values of lambda for which (lim)(xvec1)sec^(-1)((la...

    Text Solution

    |

  18. If lim(xrarr0) (e^(ax)-e^(x)-x)/(x^(2))=b (finite), then

    Text Solution

    |

  19. If lim(xrarr0)(x^3)/(sqrt(a+x)(bx-sinx))=1,agt0, then a+b is equal to

    Text Solution

    |

  20. If lim(xrarroo) xlog(e)(|(alpha//x,1,gamma),(0,1//x,beta),(1,0,1//x)|)...

    Text Solution

    |