Find the value of k so that the function f is continuous at the indicated point:
Given,
…(1)
We need to find the value of k such that f(x) is continuous at x = 2.
A function f(x) is said to be continuous at x = c if,
Left hand limit(LHL at x = c) = Right hand limit(RHL at x = c) = f(c).
Mathematically we can represent it as-
Where h is a very small number very close to 0 (h→0)
Now, let’s assume that f(x) is continuous at x = 2.
∴
As we have to find k so pick out a combination so that we get k in our equation.
In this question we take LHL = f(5)
∴
⇒ {using equation 1}
⇒
⇒
⇒
As the limit can’t be evaluated directly as it is taking 0/0 form.
So, use the formula:
Divide the numerator and denominator by -h to match with the form in formula-
Using algebra of limits, we get,
k =
∴ k =