Chapters
- Exercise 1
- Exercise 2
- Exercise 3
- Exercise 4
- Exercise 5
- Exercise 6
- Exercise 7
- Exercise 8
- Exercise 9
- Exercise 10
- Exercise 11
- Exercise 12
- Solution of exercise 1
- Solution of exercise 2
- Solution of exercise 3
- Solution of exercise 4
- Solution of exercise 5
- Solution of exercise 6
- Solution of exercise 7
- Solution of exercise 8
- Solution of exercise 9
- Solution of exercise 10
- Solution of exercise 11
- Solution of exercise 12
Exercise 1
Prove that the function
intersects the x-axis on the interval
. Can the same be said for the function:
?
Exercise 2
Given the function:
Can it be said that f(x) is bounded in the interval
?
Exercise 3
Given the function
. Can it be said that the function exists for all values in the interval
?
Exercise 4
Prove that the equation:
, has at least one solution
such that
.
Exercise 5
Given the function
. Can it be said that there is at least one point, c, inside the interval
which verifies that
?
Exercise 6
Prove that the polynomial function
has a value of zero between
and
.
Exercise 7
Prove that the equation
has at least one real solution.
Exercise 8
Prove that there is a real number, x, such that
.
Exercise 9
Given the function:
Prove that there is a point in the open interval
in which the function
has a value of
.
Exercise 10
Given the function
, determine if it is bounded superiorly and inferiorly in the interval
and indicate if it reaches its maximum and minimum values within this interval.
Exercise 11
Prove that the function
is continuous at
and prove that there exists at least one real root of the equation
.
Exercise 12
f and g are two continuous functions in
and such that
and
. Prove the existance of c withinin
such that
.
Solution of exercise 1
Prove that the function
intersects the x-axis on the interval
. Can the same be said for the function:
?
The first function is continuous at
.
.
.
Since it verifies the intermediate value theorem, at least one c belongs to the interval
and intersects the x-axis.
We cannot confirm the same of the second function because it is not continuous at
.
Solution of exercise 2
Given the function:
Can it be said that f(x) is bounded in the interval
?
Since f(x) is not continuous at
, the function is not continuous in the closed interval
, as a result, it cannot be said that the function is bounded in that interval.
Solution of exercise 3
Given the function
. Can it be said that the function exists for all values in the interval
?
The function is continuous at
since it is a polynomial function.
It is in the interval
as it is verified that
and
.
Since it verifies the intermediate value theorem, the function exists at all values in the interval
.
Solution of exercise 4
Prove that the equation:
, has at least one solution
such that
.
f(x) is continuous in 


Since it verifies the Bolzano's Theorem, there is c
such that:

Therefore there is at least one real solution to the equation
.
Solution of exercise 5
Given the function
. Can it be said that there is at least one point, c, inside the interval
which verifies that
?
f(x) is continuous in
.


The Bolzano theorem cannot be applied because it does not change sign.
Solution of exercise 6
Prove that the polynomial function
has a value of zero between
and
.
is a polynomial and therefore is continuous in the interval
.

.
There is a
such that 
Solution of exercise 7
Prove that the equation
has at least one real solution.
The function is continuous in the interval
.
.
.
Since it verifies Bolzano's theorem, there is
such that:
Therefore there is at least one real solution to the equation
.
Solution of exercise 8
Prove that there is a real number, x, such that
.
Consider the function
.
It is continuous at
.


There is a
such that:
Therefore, there is at least one real solution to the equation
.
Solution of exercise 9
Given the function:
Prove that there is a point in the open interval
in which the function
has a value of
.
The exponential function is positive at
, therefore the denominator of the function cannot be annulled.
There is only doubt of the continuity at
, which is out of the interval being studied, therefore
is continuous in
.
Consider the function g defined by
.
g is continuous on the interval
.
Since it verifies the intermediate value theorem, there is a
such that:
Solution of exercise 10
Given the function
, determine if it is bounded superiorly and inferiorly in the interval
and indicate if it reaches its maximum and minimum values within this interval.
The function is continuous in the interval
, as a result, it can be affirmed that it is bounded in that interval.
As well as being continuous in the interval
, it has fulfilled the extreme value theorem, which affirms that it attains at least one maximum and absolute minimum in the interval
.
Solution of exercise 11
Prove that the function
is continuous at
and prove that there exists at least one real root of the equation
.
The function is continuous since it is the sum of continuous functions.


Since it verifies the intermediate value theorem, there is a
such that:
Therefore, there is at least one real solution to the equation
.
Solution of exercise 12
f and g are two continuous functions in
and such that
and
. Prove the existance of c withinin
such that
.
h is the function defined by
.
Since f and g are continuous in
, the function h also is.
Since it verifies the intermediate value theorem, there is a
such that:









Derivative of denominator is wrong
Good catch—thanks for pointing that out! We’ll double-check the derivative in that section and make any necessary corrections. Really appreciate you taking the time to flag it. 👍
Thank you
Thank you Abbas! Good luck with your studies!
With regard to the Zero Over a Number item, is there a mis-statement? It’s immediately followed by “If a number is divided by zero which means that the numerator is zero and the denominator is the number, then the result is zero.”
Hi Mark,
You’re absolutely right to raise the question — there does appear to be a misstatement in that sentence. The phrase “If a number is divided by zero, which means that the numerator is zero and the denominator is the number…” is indeed misleading and should be corrected.
To clarify:
Zero divided by a number (e.g. 0 ÷ 5) equals 0.
A number divided by zero (e.g. 5 ÷ 0) is undefined.
We’ll update the sentence to reflect the correct mathematical explanation. We appreciate you catching that and helping us improve the accuracy of the content!
There is more than one size of infinity, though. What if you multiply the infinity of the whole numbers (Aleph-0) by the infinity of the real numbers (fraktur-c)?
Thanks a lot to you for this essentiol article.
Hi Piyash! Thanks for your comment, great to hear that you found this useful!
Very nice