How do I take the cube root of -8?

Question

I'm supposed to take the cube root of negative eight; how do I do this without a calculator (or decimals?)

Answer 1

(- 8) ^(1/3)
= ( 8 i ² )^(1/3)
= 2 x (-1)
= - 2

Answer 2

You need to find the number so that that number times itself times itself again is equal to your answer. First of all -2 is the answer since -2 x -2 = 4 and 4 x -2 = -8 Another way to think about this is to take out the negative. The cube root of (xy) is the cube root of x time the cube root of y. So think of the 8 as (-1 x 8). The cube root of -1 is -1. The cube root of 8 is 2. The cube root of (-1 x 8) is (-1 x 2) = -2

Answer 3

2*2*2=8 so the cubed root of 8 is 2. The cubed root of -8 would be -2, because
-2*-2=4, then 4*-2=-8. I hope I am remembering this right.

Answer 4

-2 * -2 * -2 = -8
2^3 is the cube root of -8

Answer 5

What you're trying to find is the number that when multiplied by itself 3 times would be -8.

3 x 3 x 3=27 wrong

2 x 2 x 2=8 wrong

-2 x -2 x -2= -8 right

Answer 6

the cube root of -8 is -2, since -2 x -2 x -2 = -8

Answer 7

you memorize or factor

what are the prime facors of 8? of -8?

8=2*2*2 = 2^3
-8 = -2*-2*-2 = (-2)^3

cubed root of a^3 = a
cubed root of -8 = cubed root of (-2)^3 = -2

Answer 8

what number multiplied by itself three times equals -8

it is mostly a memorization thing or factor it
-8
4*-2
-2*-2*-2

so -2 is the cube root of -8

Answer 9

find a number that, when multiplied by itself 3 times equals - 8

so, you know that it has to be a negative number, because the root is odd -- and the number is negative . . .

so, start small and work your way up.

-1 x -1 x -1 = -1

-2 x -2 x -2 = -8

yay! we got the answer!

Answer 10

as it is cubed, you do not have an irrational answer, the answer will be -2, -2x-2 is 4, 4x-2 is -8.