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Helpppppppppppppppppppppppppppppppppppp

Helpppppppppppppppppppppppppppppppppppp-example-1

2 Answers

0 votes
First we rewrite the expression:
root (8x ^ 7y ^ 8)
(8x ^ 7y ^ 8) ^ (1/2)
Properties of exponents:
(8 ^ (1/2) x ^ (7/2) y ^ (8/2)
We rewrite:
(8 ^ (1/2) x ^ (7/2) y ^ 4
(2 * 2 ^ (1/2) x ^ 3y ^ 4x ^ (1/2)
(2 * x ^ 3 * y ^ 4 * (2x) ^ (1/2)
Answer:
(2*x^3*y^4*(2x)^(1/2)
option 3
User Giulio Bambini
by
8.0k points
4 votes
To take out terms outside the radical we need to divide the power of the term by the index of the radical; the quotient will be the power of the term outside the radical, and the remainder will be the power of the term inside the radical.
First, lets factor 8:

8=2 ^(3)
Now we can divide the power of the term, 3, by the index of the radical 2:

(3)/(2) = 1 with a remainder of 1
Next, lets do the same for our second term
x^(7):

(7)/(2) = 3 with a remainder of 1
Again, lets do the same for our third term
y^(8):

(8)/(2) =4 with no remainder, so this term will come out completely.

Finally, lets take our terms out of the radical:

\sqrt{8x^(7) y^(8) }= \sqrt{ 2^(3) x^(7) y^(8) } =2 x^(3) y^(4) √(2x)

We can conclude that the correct answer is the third one.

User Michael Hodel
by
7.4k points