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Because the cube of a positive number is positive and the cube of a negative number is negative.
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Every number has THREE cube roots. However, (at least) two of the three are complex numbers.
For example, the cube roots of 8 are 2, (-1 + √3 i) and (-1 - √3 i) with i² = -1:
2³ = 2 × 2 × 2 = 8
(-1 + √3 i)³ = (-1 + √3 i)(-1 + √3 i)(-1 + √3 i)
= (-1 + √3 i)((-1)² - 2√3 i + 3i²)
= (-1 + √3 i)(1 - 2√3 i -3)
= (-1 + √3 i)(-2 - 2√3 i)
= (-1 + √3 i)(-1 - √3 i)2
= ((-1)² - 3i²)2
= (1 + 3)2
= 4 × 2 = 8
(-1 - √3 i)³ = (-1 - √3 i)(-1 - √3 i)(-1 - √3 i)
= (-1 - √3 i)((-1)² + 2√3 i + 3i²)
= (-1 - √3 i)(1 + 2√3 i -3)
= (-1 - √3 i)(-2 + 2√3 i)
= (-1 - √3 i)(-1 + √3 i)2
= ((-1)² - 3i²)2
= (1 + 3)2
= 4 × 2 = 8
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What is the abbreviation for cube root?
"cbrt" is acceptable abbreviation of cube root, although it is much easier to write "^(1/3)", which is the one-third power, or the cube root. They are mathematically identical.
The cube root of this number is one more than the smallest prime?
The cube root of this number is one more than the smallest prime
What expression has a value between 14 and 15?
There are infinitely many possible expressions. One such is 3000^(1/3), that is, the cube root of 3000.
How do you find the edge of a cube if the volume is 200?
The equation of the volume of a cube is s^3, where 's' is the length of one edge. So the edge would be the cubed root of the volume. In your case, the cube root of 200. Which is 5.848 (approx).
How do you find the volume of cube only knowing its surface area?
Divide the surface area by six. That will give you the area of one face, which will be a perfect square. The square root of that number will give you the length of a side. The cube of the side will be the volume.
