The cube root of 40 in simplified radical form is equal to 2∛5. The value of cube root of 40 is 3.42 corrected up to two decimal places. Note that a number m is called a cube root of 40 if m3 = 40. So it is a root of the cubic equation x3=40, so there are three cube roots of 40.
Some facts are listed below:
- Cube root of 40 in simplified radical form is 2∛5.
- ∛40 = 2∛5.
- 40 is not a prefect cube number.
- 401/3 is the exponential for of the cube root of 40.
- Value of cube root of 40 is 3.4199 (in decimal form) corrected up to 4 decimal places.
- cube of 40: 40×40×40 = 64000.
Table of Contents
What is the Cube Root of 40?
To find the cube root of 40, we will express the number 40 as a product of numbers at least one of them will be perfect cubes. We can write 40 as follows:
40 = 8×5.
Here 8 is a perfect cube as 8 = 23.
Taking cube root on both sides, we obtain that
$\sqrt[3]{40} = \sqrt[3]{8 \times 5}$ ⇒ $\sqrt[3]{40} = \sqrt[3]{8} \times \sqrt[3]{5}$ using the rule: ∛ab = ∛a ∛b. ⇒ $\sqrt[3]{40} = 2 \times \sqrt[3]{5}$. |
That is, ∛40 = 2∛5.
So the cube root of 40 in its simplified radical form is equal to 2∛5.
By Prime Factorization
The prime factorization of 40 is given as follows:
40 = 2 × 2 × 2 × 5.
So $\sqrt[3]{40} = \sqrt[3]{2 \times 2 \times 2 \times 5}$
Make a grouping of 3 identical numbers, so we obtain that
$\sqrt[3]{40} = \sqrt[3]{2 \times 2 \times 2} \times \sqrt[3]{5}$ ⇒ ∛40 = 2 × ∛5 ⇒ ∛40 = 2∛5. |
So the cube root of 40 by prime factorization method is equal to 2∛5, and it is its simplest radical form.
More cube roots:
Value of Cube Root of 40
As we know that cube root of 40 is given by ∛40 = 2∛5, and the value of ∛5 is 1.71 approximately, so we obtain that
∛40 = 2 × 1.71 = 3.42.
Therefore, 3.42 is the value of cube root of 40.
Also Read: cube root of 81
Is 40 a Perfect Cube
Answer: Note that 40 will be a prefect cube number only if its cube root is a whole number. We know that ∛40 = 2∛5 is not a whole number. This proves that the number 40 is not a perfect cube.
Is Cube Root of 40 Rational
Answer: The cube root of 40 is 2∛5, and the number ∛5 is irrational. Therefore, we conclude that cube root of 40 is not a rational number.
FAQs
Answer: The cube root of 40 in its simplest radical form is equal to 2∛5.
Answer: As ∛40 = 2∛5 is not an integer, 40 is not a perfect cube number.
This article is written by Dr. T. Mandal, Ph.D in Mathematics. On Mathstoon.com you will find Maths from very basic level to advanced level. Thanks for visiting.