English

The value of limx→-∞5x2+4x+75x+4 is ______ -

Advertisements
Advertisements

Question

The value of `lim_{x→-∞} (sqrt(5x^2 + 4x + 7))/(5x + 4)` is ______ 

Options

  • `-1/sqrt5`

  • 0

  • `1/sqrt5`

  • 1

MCQ
Fill in the Blanks

Solution

The value of `lim_{x→-∞} (sqrt(5x^2 + 4x + 7))/(5x + 4)` is `underline(-1/sqrt5)`.

Explanation:

Put x = -y

As x → -∞, y → ∞

∴`lim_{x→-∞} (sqrt(5x^2 + 4x + 7))/(5x + 4) = lim_{y→ ∞}sqrt(5(-y)^2 - 4y + 7)/(-5y + 4)`

= `lim_{y→ ∞} sqrt(5 - 4/y + 7/y^2)/(-5 + 4/y)`

= `sqrt5/-5`

= `-1/sqrt5`

shaalaa.com
Limits of Exponential and Logarithmic Functions
  Is there an error in this question or solution?
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×