Cube & Cubeth Root

What is Cube?

A cube of a number is the result of multiplying that number by itself three times. It is expressed mathematically as 𝑛³ , where 𝑛ⁿ is any real number. For example, the cube of 4 is 4³

What is Cube Roots?

The cube root of a number is a value that, when cubed, gives the original number. It is denoted as 𝑛3​. For instance, the cube root of 64 is ³√64=4, because 4³ =64

Properties of Cubes and Cube Roots

Cubes and cube roots possess unique mathematical properties that are essential for both theoretical studies and practical applications. Here are the key properties for each:

Properties of Cubes

1. Preservation of Sign:

   • The cube of a positive number is positive, and the cube of a negative number is negative. This differs from squaring, where both positive and negative numbers yield a positive square.

2. Odd and Even Nature:

   • The cube of an odd number remains odd, and the cube of an even number remains even, maintaining the parity of the original number.

3. Sum of Cubes Formula:

   • The sum of the cubes of the first 𝑛n natural numbers is given by the formula:
     1³+2³+3³+…+𝑛³=(𝑛(𝑛+1)/2)²
   • This formula is a square of the sum of the first $n$ natural numbers, illustrating a deep algebraic identity.

4. Multiplicative Property:

   • The cube of a product of numbers is equal to the product of their cubes:
     (𝑎𝑏𝑐)³=𝑎³×𝑏³×𝑐³

Properties of Cube Roots

1. Inverse Operation:

   • The cube root is the inverse operation of cubing a number. If 𝑥³=𝑦, then ³√y=x.

2. Behavior with Negative Numbers:

   • Unlike square roots, cube roots can be taken of negative numbers. For example, ³√−8=−2

3. Distribution over Multiplication:

   • Cube roots can be distributed over multiplication:
     ³√𝑎𝑏𝑐=³√𝑎׳√𝑏׳√𝑐

4. Root of a Fraction:

   • The cube root of a fraction is the fraction of the cube roots:
     ³√𝑎/b = ³√𝑎/³√𝑏​

5. Continuity:

   • Cube root functions are continuous for all real numbers, meaning they do not have any breaks or jumps in their graphs.

Cube Root Formula

The cube root of a number 𝑎 provides a value 𝑏 such that when 𝑏 is cubed, it returns 𝑎. Mathematically, this relationship is expressed as: ³√𝑎=𝑏This equation holds true under the condition that: 𝑎=𝑏³This relationship is particularly useful when determining the cube root of perfect cubes, where 𝑎 and 𝑏

Number	Cubes
1	1
2	8
3	27
4	64
5	125
6	216
7	343
8	512
9	729
10	1000

Cube Root 1 to 30

Number	Cube Root (3√)
1	1.000
2	1.260
3	1.442
4	1.587
5	1.710
6	1.817
7	1.913
8	2.000
9	2.080
10	2.154
11	2.224
12	2.289
13	2.351
14	2.410
15	2.466
16	2.520
17	2.571
18	2.621
19	2.668
20	2.714
21	2.759
22	2.802
23	2.844
24	2.884
25	2.924
26	2.962
27	3.000
28	3.037
29	3.072
30	3.107

How to Find Cube Root of a Number?

Step 1: Prime Factorization

Begin by breaking down the number into its prime factors. This involves dividing the number by the smallest prime number (starting with 2) and continuing the process with the quotient until only prime numbers are left.

Step 2: Group the Factors

Organize the resulting prime factors into groups, each containing three identical factors. This step is crucial because the cube root of a number will be the product of factors from each group.

Step 3: Calculate the Cube Root

Multiply one factor from each group to find the cube root. If any factors remain that cannot be grouped into threes, then the number is not a perfect cube, and an exact cube root (in whole numbers) cannot be determined.

Question 1: Solve the Equation

Solve the equation 2𝑥−6=16

Answer: Add 6 to both sides: 2𝑥=22 Divide by 2: 𝑥=11Final Answer: 𝑥=11

Question 2: Calculate Compound Interest

Calculate the compound interest on $1000 for 2 years at an annual interest rate of 5%, compounded annually.

Answer: Use the formula for compound interest: 𝐴=𝑃(1+𝑟)𝑛A=P(1+r)n Where:

• 𝑃=1000
• 𝑟=0.05
• 𝑛=2

Calculate:
𝐴=1000(1+0.05)²
𝐴=1000(1.05)² 𝐴=1000×1.1025=1102.5

Final Answer: The compound interest is $1102.5.

Question 3: Convert Temperatures

Convert 68°F to Celsius using the formula 𝐶=5/9(𝐹−32)C=95​(F−32).

Answer: Plug in the Fahrenheit value: 𝐶=5/9(68−32)

𝐶=5/9(36)

𝐶=20

Final Answer: 20°C

FAQs

What is Cube or Cubed Root?

A cube is a number raised to the power of three, expressed as 𝑛³. A cube root is the inverse, finding a number 𝑛n that when cubed gives the original number, denoted as ³√×

What is the Cube Root Formula?

The cube root formula to find 𝑛n from 𝑛³=𝑥 is expressed as ³√× = nIt calculates the number 𝑛 whose cube equals 𝑥.

What is the 729 Cube Root?

The cube root of 729 is 9, since 9³=729 This means ³√729=9.

What is a Cube of 4?

The cube of 4 is 64, calculated as 4³=4×4×4=64

What is Cube 1 to 10?

Cubes from 1 to 10 are: 1, 8, 27, 64, 125, 216, 343, 512, 729, and 1000. These represent 𝑛³ for 𝑛n from 1 to 10.

Is 30 a Cube Number?

No, 30 is not a cube number. There is no integer 𝑛n such that 𝑛³=30. The cube numbers closest to 30 are 27 (3³) and 64 (4³)