Question
In the following, find the value of the constant k so that the given function is continuous at the indicated point:
$\text{f(x)}=\begin{cases}\frac{\text{x}^2-25}{\text{x}-5},&\text{x}\neq5\\\text{k},&\text{x}=5\end{cases}\text{at x} =5$

Answer

Given,
$\text{f(x)}=\begin{cases}\frac{\text{x}^2-25}{\text{x}-5},&\text{x}\neq5\\\text{k},&\text{x}=5\end{cases}$
$\Rightarrow\text{f(x)}=\begin{cases}\frac{(\text{x}-5)(\text{x}+5)}{\text{x}-5},&\text{x}\neq5\\\text{k},&\text{x}=5\end{cases}$
$\Rightarrow\text{f(x)}=\begin{cases}{\text{x}-5},&\text{x}\neq5\\\text{k},&\text{x}=5\end{cases}$
If f(x) is continuous at x = 5, then,
$\lim_\limits{\text{x}\rightarrow5}\text{f(x)}=\text{f}(5)$
$\Rightarrow\lim_\limits{\text{x}\rightarrow5}\text{(x}+5)=\text{k}$
$\Rightarrow\text{k}=5+5=10$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

If P(A) = 0.4, P(B) = 0.3 and $\text{P}\Big(\frac{\text{B}}{\text{A}}\Big)=0.5$ find $\text{P}(\text{A}\cap\text{B})$ and $\text{P}\Big(\frac{\text{A}}{\text{B}}\Big).$
A, B, and C are independent witness of an event which is known to have occurred. A speaks the truth three times out of four, B four times out of five and C five times out of six. What is the probability that the occurrence will be reported truthfully by majority of three witnesses?
If $x^2+y^2=t-\frac{1}{t}$ and $x^4+y^4=t^2+\frac{1}{t^2}$, then prove that $x \frac{d^2 y}{d x^2}+2 \frac{d y}{d x}=0$
Prove that $\cot\Big(\frac{\pi}{4}-2\cot^{-1}3\Big)=7$
A binary operation * is defined on the set R of all real numbers by the rule $\text{a}\times\text{b}=\sqrt{\text{a}^2+\text{b}^2}\ \forall\text{ a, b}\in\text{R}$.
Write the identity element for * on R.
Solve the following linear programming problem graphically:
Maximise Z = 4x + y subject to the constraints: 
x + y $\le$ 50
3x + y $\le$ 90
x $\ge$ 0, y $\ge$ 0
Write a value of $\int\frac{\cos\text{x}}{3+2\sin\text{x}}\text{ dx}$
Write the difference between maximum and minimum values of $\sin^{-1}\text{x}$ for $\text{x}\in[-1,1].$
Find the value of k for which $\text{f(x)}=\begin{cases}\frac{1-\cos4\text{x}}{8\text{x}^2},&\text{when x}\neq0\\\text{k},&\text{when x}=0\end{cases}$ is continous at x = 0.
A dice is thrown thrice. A success is 1 or 6 in a throw. Find the mean and variance of the number of successes.