Simplify.

Remove all perfect squares from inside the square root. Assume
\[x\] is positive.
\[\sqrt{54x^7}=\]

1 answer

To simplify \(\sqrt{54x^7}\), we start by breaking down the expression under the square root into its prime factors and separating the perfect squares from the non-perfect squares.

  1. Factor 54: \[ 54 = 2 \times 27 = 2 \times 3^3 \]

  2. Rewrite the expression: \[ 54x^7 = 2 \times 3^3 \times x^7 \]

  3. Identify perfect squares:

    • From \(3^3\), we can extract \(3^2\) as a perfect square: \[ 3^3 = 3^2 \times 3^1 \]
    • For \(x^7\), we can extract \(x^6\) as a perfect square: \[ x^7 = x^6 \times x^1 \]
  4. Put it all together inside the square root: \[ \sqrt{54x^7} = \sqrt{(2 \times 3^2 \times x^6) \times (3^1 \times x^1)} = \sqrt{(2 \times 9 \times x^6) \times (3 \times x)} \]

  5. Use the property of square roots to separate perfect squares from non-perfect squares: \[ \sqrt{54x^7} = \sqrt{2} \cdot \sqrt{9} \cdot \sqrt{x^6} \cdot \sqrt{3} \cdot \sqrt{x} \]

  6. Calculate the square roots of the perfect squares:

    • \(\sqrt{9} = 3\)
    • \(\sqrt{x^6} = x^3\)
  7. Combine the simplified parts: \[ \sqrt{54x^7} = 3x^3\sqrt{2 \times 3 \times x} = 3x^3\sqrt{6x} \]

Thus, the simplified form is: \[ \sqrt{54x^7} = 3x^3\sqrt{6x} \]