馃憠 Try now NerdPal! Our new math app on iOS and Android

Find the limit $\lim_{x\to4}\left(\frac{3-\sqrt{5+x}}{1-\sqrt{5-x}}\right)$

Step-by-step Solution

Go!
Math mode
Text mode
Go!
1
2
3
4
5
6
7
8
9
0
a
b
c
d
f
g
m
n
u
v
w
x
y
z
.
(◻)
+
-
×
◻/◻
/
÷
2

e
π
ln
log
log
lim
d/dx
Dx
|◻|
θ
=
>
<
>=
<=
sin
cos
tan
cot
sec
csc

asin
acos
atan
acot
asec
acsc

sinh
cosh
tanh
coth
sech
csch

asinh
acosh
atanh
acoth
asech
acsch

Final Answer

$-\frac{1}{3}$
Got another answer? Verify it here!

Step-by-step Solution

Specify the solving method

1

If we directly evaluate the limit $\lim_{x\to 4}\left(\frac{3-\sqrt{5+x}}{1-\sqrt{5-x}}\right)$ as $x$ tends to $4$, we can see that it gives us an indeterminate form

$\frac{0}{0}$
2

We can solve this limit by applying L'H么pital's rule, which consists of calculating the derivative of both the numerator and the denominator separately

$\lim_{x\to 4}\left(\frac{\frac{d}{dx}\left(3-\sqrt{5+x}\right)}{\frac{d}{dx}\left(1-\sqrt{5-x}\right)}\right)$
3

After deriving both the numerator and denominator, the limit results in

$\lim_{x\to4}\left(\frac{-\left(5+x\right)^{-\frac{1}{2}}}{\left(5-x\right)^{-\frac{1}{2}}}\right)$
4

Applying the property of exponents, $\displaystyle a^{-n}=\frac{1}{a^n}$, where $n$ is a number

$\lim_{x\to4}\left(\frac{-1}{\left(5-x\right)^{-\frac{1}{2}}\sqrt{5+x}}\right)$
5

Evaluate the limit $\lim_{x\to4}\left(\frac{-1}{\left(5-x\right)^{-\frac{1}{2}}\sqrt{5+x}}\right)$ by replacing all occurrences of $x$ by $4$

$\frac{-1}{\left(5-4\right)^{-\frac{1}{2}}\sqrt{5+4}}$
6

Subtract the values $5$ and $-4$

$\frac{-1}{1^{-\frac{1}{2}}\sqrt{5+4}}$
7

Add the values $5$ and $4$

$\frac{-1}{1^{-\frac{1}{2}}\sqrt{9}}$
8

Calculate the power $1^{-\frac{1}{2}}$

$\frac{-1}{\sqrt{9}}$
9

Calculate the power $\sqrt{9}$

$-\frac{1}{3}$
10

Divide $-1$ by $3$

$-\frac{1}{3}$

Final Answer

$-\frac{1}{3}$

Exact Numeric Answer

$-0.3333$

Explore different ways to solve this problem

Solving a math problem using different methods is important because it enhances understanding, encourages critical thinking, allows for multiple solutions, and develops problem-solving strategies. Read more

Limits by Direct SubstitutionLimits by L'H么pital's ruleLimits by FactoringLimits by Rationalizing

Give us your feedback!

Function Plot

Plotting: $\frac{3-\sqrt{5+x}}{1-\sqrt{5-x}}$

SnapXam A2
Answer Assistant

beta
Got a different answer? Verify it!

Go!
1
2
3
4
5
6
7
8
9
0
a
b
c
d
f
g
m
n
u
v
w
x
y
z
.
(◻)
+
-
×
◻/◻
/
÷
2

e
π
ln
log
log
lim
d/dx
Dx
|◻|
θ
=
>
<
>=
<=
sin
cos
tan
cot
sec
csc

asin
acos
atan
acot
asec
acsc

sinh
cosh
tanh
coth
sech
csch

asinh
acosh
atanh
acoth
asech
acsch

How to improve your answer:

Your Math & Physics Tutor. Powered by AI

Available 24/7, 365.

Unlimited step-by-step math solutions. No ads.

Includes multiple solving methods.

Support for more than 100 math topics.

Premium access on our iOS and Android apps as well.

20% discount on online tutoring.

Choose your subscription plan:
Have a promo code?
Pay $39.97 USD securely with your payment method.
Please hold while your payment is being processed.
Create an Account