Substitute and Check: First, let's try to directly substitute the value of x with −4 into the function to see if it results in an indeterminate form.Substitute −4 for x in (x2−16)/(x2+4x).limx→−4(x2−16)/(x2+4x)= ((\-4)^2 - 16)/((\-4)^2 + 4(\-4))= (16−16)/(16−16)= 0/0We get an indeterminate form of 0/0, which means we need to simplify the expression further to find the limit.
Factor Numerator and Denominator: Since we have an indeterminate form, we can try to factor the numerator and the denominator to see if any common factors can be canceled out.Factor the numerator (x2−16) and the denominator (x2+4x).The numerator is a difference of squares and can be factored as (x+4)(x−4).The denominator can be factored by taking x common, resulting in x(x+4).So the expression becomes:limx→−4x(x+4)(x+4)(x−4)
Cancel Common Factor: Now, we can cancel out the common factor (x+4) from the numerator and the denominator.limx→−4x(x+4)(x+4)(x−4)=limx→−4xx−4Now that the expression is simplified, we can substitute −4 for x again to find the limit.
Substitute and Simplify: Substitute −4 for x in the simplified expression (x−4)/x.limx→−4xx−4= \frac{−4 - 4}{−4}= \frac{−8}{−4}= 2The limit exists and is equal to 2.