All Exams Test series for 1 year @ ₹349 only
Question

Consider the two functions $f_1(x) = \frac{x^2 - 4}{x - 2}$ and $f_2(x) = x^2 - 2x + 2$. Which of the following is the value of $(f_1(x) + f_2(x))$ as $x \to 2$?

The correct answer is
6

Limit Calculation for Sum of Functions

The problem asks for the limit of the sum of two functions, $f_1(x)$ and $f_2(x)$, as $x$ approaches 2.

Given functions:

  • $f_1(x) = \frac{x^2 - 4}{x - 2}$
  • $f_2(x) = x^2 - 2x + 2$

Evaluating $f_1(x)$ as $x \to 2$

The function $f_1(x)$ is undefined at $x=2$ (indeterminate form $\frac{0}{0}$). We simplify it first:

$f_1(x) = \frac{x^2 - 4}{x - 2} = \frac{(x - 2)(x + 2)}{x - 2}$

For $x \neq 2$, we can cancel the $(x - 2)$ terms:

$f_1(x) = x + 2$

Now, we find the limit:

$\lim_{x \to 2} f_1(x) = \lim_{x \to 2} (x + 2) = 2 + 2 = 4$

Evaluating $f_2(x)$ as $x \to 2$

$f_2(x)$ is a polynomial function, so we can directly substitute $x=2$ to find its limit:

$\lim_{x \to 2} f_2(x) = \lim_{x \to 2} (x^2 - 2x + 2) = (2)^2 - 2(2) + 2$

$= 4 - 4 + 2 = 2$

Finding the Limit of the Sum $(f_1(x) + f_2(x))$

The limit of a sum is the sum of the limits, provided the individual limits exist:

$\lim_{x \to 2} (f_1(x) + f_2(x)) = \lim_{x \to 2} f_1(x) + \lim_{x \to 2} f_2(x)$

Substituting the calculated limits:

$= 4 + 2 = 6$

Conclusion

The value of $(f_1(x) + f_2(x))$ as $x \to 2$ is 6.

Was this answer helpful?

Important Questions from Limits

  1. The limit of the function f (x, y) = x + y - 6 at x = 1; y = 2 is ?

  2. The value of \(\mathop {\lim }\limits_{x \to 2} \frac{{{x^2} - 4}}{{3x - 6}}\)  is:

  3. Value of \(\mathop {\lim }\limits_{x \to 0} \frac{{1 - \cos x}}{{x\sin x}}\)

  4. The value of \(\mathop {\lim }\limits_{x \to 0} \left( {\frac{1}{x} - \frac{1}{{\sin x}}} \right)\)

  5. \(\mathop {\lim }\limits_{x \to - 5} \frac{{\sqrt {\left( {2x + 35} \right)} - 5}}{{x + 5}}\)
Need Expert Advice?

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App