Myrna was asked to create an equivalent form of the rational expression 56k^7-14k^3+14/7k^3 Which of the following is a correct equivalent form?

1 answer

To simplify the rational expression \( \frac{56k^7 - 14k^3 + 14}{7k^3} \), we can start by factoring out the numerator and then dividing each term by the denominator.

  1. Factor the numerator:

    The numerator is \( 56k^7 - 14k^3 + 14 \). We can factor out the greatest common factor (GCF) from the first two terms:

    \[ 56k^7 - 14k^3 + 14 = 14(4k^7 - k^3 + 1) \]

    This gives us:

    \[ \frac{14(4k^7 - k^3 + 1)}{7k^3} \]

  2. Divide by the denominator:

    Now, we can simplify the expression further by dividing both the numerator and denominator by 7:

    \[ = \frac{14}{7} \cdot \frac{(4k^7 - k^3 + 1)}{k^3} \]

    Simplifying \( \frac{14}{7} \) gives us 2:

    \[ = 2 \cdot \frac{(4k^7 - k^3 + 1)}{k^3} \]

  3. Break down the fraction:

    Now we can separate \( \frac{(4k^7 - k^3 + 1)}{k^3} \):

    \[ = 2 \left( \frac{4k^7}{k^3} - \frac{k^3}{k^3} + \frac{1}{k^3} \right) \]

    Simplifying each term:

    • \( \frac{4k^7}{k^3} = 4k^{7-3} = 4k^4 \)
    • \( \frac{k^3}{k^3} = 1 \)
    • \( \frac{1}{k^3} = k^{-3} \)

    So the expression becomes:

    \[ 2 \left( 4k^4 - 1 + \frac{1}{k^3} \right) \]

  4. Final equivalent form:

    We can then express it as:

    \[ 8k^4 - 2 + \frac{2}{k^3} \]

So, an equivalent form of the rational expression \( \frac{56k^7 - 14k^3 + 14}{7k^3} \) is

\[ 8k^4 - 2 + \frac{2}{k^3} \]