Which of the following expressions is not a factor of 6x^3−35x^2−69x+140 ? Use long division to solve.

1 answer

To determine which expression is not a factor of the polynomial \(6x^3 - 35x^2 - 69x + 140\), we can perform polynomial long division with each given expression. However, since you didn't provide the specific expressions, I'll explain how to perform the long division and indicate how to identify a non-factor.

Steps for Polynomial Long Division:

  1. Divide the leading terms: Divide the leading term of the polynomial by the leading term of the divisor.

  2. Multiply: Multiply the entire divisor by the result obtained in step 1.

  3. Subtract: Subtract the result from the original polynomial.

  4. Bring down the next term: If there are more terms, bring down the next term from the polynomial.

  5. Repeat: Continue the process until all terms have been brought down.

Determining Non-Factors:

  • If, after performing the long division, you obtain a remainder of 0, then the divisor is a factor of the polynomial.
  • If there is a remainder that is not 0, then the divisor is not a factor of the polynomial.

Example:

Suppose one of the expressions provided is \(x - 2\).

Let's perform long division on \(6x^3 - 35x^2 - 69x + 140\) by \(x - 2\):

  1. Divide \(6x^3\) by \(x\): \[ 6x^2 \]

  2. Multiply \(x - 2\) by \(6x^2\): \[ 6x^3 - 12x^2 \]

  3. Subtract: \[ (6x^3 - 35x^2) - (6x^3 - 12x^2) = -35x^2 + 12x^2 = -23x^2 \] Bring down the next term \(-69x\): \[ -23x^2 - 69x \]

  4. Divide \(-23x^2\) by \(x\): \[ -23x \]

  5. Multiply \(x - 2\) by \(-23x\): \[ -23x^2 + 46x \]

  6. Subtract: \[ (-23x^2 - 69x) - (-23x^2 + 46x) = -69x - 46x = -115x \] Bring down the \(+140\): \[ -115x + 140 \]

  7. Divide \(-115x\) by \(x\): \[ -115 \]

  8. Multiply \(x - 2\) by \(-115\): \[ -115x + 230 \]

  9. Subtract: \[ (-115x + 140) - (-115x + 230) = 140 - 230 = -90 \]

Since we ended up with a remainder of \(-90\), \(x - 2\) is not a factor of \(6x^3 - 35x^2 - 69x + 140\).

You can repeat this process for each expression provided. Let me know if you have specific expressions listed so we can evaluate them directly.