Evaluate the limit:

[tex]\[ \lim _{x \rightarrow 8} \frac{3x^2 - 9x - 162}{x^2 + 11x + 30} \][/tex]

Round your answer to two decimal places, include the decimal places even if they are zeros. If the limit does not exist, enter DNE.



Answer :

Let's evaluate the limit
[tex]\[ \lim _{x \rightarrow 8} \frac{3 x^2 - 9 x - 162}{x^2 + 11 x + 30}. \][/tex]

First, we need to examine the function given in the limit:
[tex]\[ f(x) = \frac{3 x^2 - 9 x - 162}{x^2 + 11 x + 30}. \][/tex]

Evaluate the numerator and denominator at [tex]\( x = 8 \)[/tex]:
[tex]\[ \text{Numerator} = 3(8)^2 - 9(8) - 162 = 192 - 72 - 162 = -42, \][/tex]
[tex]\[ \text{Denominator} = (8)^2 + 11(8) + 30 = 64 + 88 + 30 = 182. \][/tex]

Thus, the function at [tex]\( x = 8 \)[/tex] is:
[tex]\[ f(8) = \frac{-42}{182}. \][/tex]

Next, we shall simplify this fraction:
[tex]\[ \frac{-42}{182} = -\frac{42}{182}. \][/tex]

To find the simplest form, we need to determine the greatest common divisor (GCD) of 42 and 182. The GCD of 42 and 182 is 14, so we have:
[tex]\[ - \frac{42 \div 14}{182 \div 14} = -\frac{3}{13}. \][/tex]

Thus,
[tex]\[ f(8) = -\frac{3}{13}. \][/tex]

Finally, let's round this result to two decimal places. Converting [tex]\(-\frac{3}{13}\)[/tex] to its decimal form:
[tex]\[ - \frac{3}{13} \approx -0.230769230769\ldots \approx -0.23. \][/tex]

Therefore, the limit is:
[tex]\[ \lim _{x \rightarrow 8} \frac{3 x^2 - 9 x - 162}{x^2 + 11 x + 30} = -\frac{3}{13}, \][/tex]
which rounds to two decimal places as:
[tex]\[ -0.23. \][/tex]

So, the final answer is:
[tex]\[ -\frac{3}{13}, -0.23. \][/tex]