Use long divison to divide the polynomial -30x^6 + 48x^5 + 50x - 80 by 5x - 8

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To perform long division of the polynomial \(-30x^6 + 48x^5 + 50x - 80\) by \(5x - 8\), we will follow these steps:

  1. Divide the leading term of the dividend by the leading term of the divisor.
  2. Multiply the entire divisor by this result.
  3. Subtract this from the original polynomial (the dividend).
  4. Repeat the process with the new polynomial (the remainder) until the degree of the remainder is less than the degree of the divisor.

Let's start the division:

Step 1: Divide the leading terms

  • The leading term of the dividend is \(-30x^6\).
  • The leading term of the divisor is \(5x\).

\[ \frac{-30x^6}{5x} = -6x^5 \]

Step 2: Multiply the divisor by \(-6x^5\)

\[ (-6x^5)(5x - 8) = -30x^6 + 48x^5 \]

Step 3: Subtract from the original polynomial

Now we perform the subtraction: \[ (-30x^6 + 48x^5 + 50x - 80) - (-30x^6 + 48x^5) = 50x - 80 \]

Step 4: Repeat the process with the new polynomial \(50x - 80\)

Now we take \(50x - 80\) and divide it by \(5x - 8\).

Divide the leading terms:

\[ \frac{50x}{5x} = 10 \]

Multiply the divisor by \(10\):

\[ 10(5x - 8) = 50x - 80 \]

Subtract:

\[ (50x - 80) - (50x - 80) = 0 \]

Since we reached a remainder of \(0\), we stop here.

Final Result

The division shows that: \[ -30x^6 + 48x^5 + 50x - 80 = (5x - 8)(-6x^5 + 10) \]

Thus, the quotient of the division is: \[ \boxed{-6x^5 + 10} \]

And there is no remainder.