Perform the operation(s) and simplify completely. 8x3−12x2+18x−272x−3−(x2+4x) Identify A, B, and C in your answer, Ax2+Bx2+C

1 answer

To simplify the expression \( 8x^3 - 12x^2 + 18x - 27 - 2x - 3 - (x^2 + 4x) \), we will first distribute the negative sign through the parentheses.

The original expression is:

\[ 8x^3 - 12x^2 + 18x - 27 - 2x - 3 - (x^2 + 4x) \]

Distributing the negative sign gives:

\[ 8x^3 - 12x^2 + 18x - 27 - 2x - 3 - x^2 - 4x \]

Now, combine like terms. Start with the \(x^3\) terms, then \(x^2\) terms, followed by \(x\) terms, and finally the constant terms:

  1. Cubic term: \(8x^3\) (there's only one)
  2. Quadratic terms: \(-12x^2 - x^2 = -13x^2\)
  3. Linear terms: \(18x - 2x - 4x = 12x\)
  4. Constant terms: \(-27 - 3 = -30\)

Putting it all together, the expression simplifies to:

\[ 8x^3 - 13x^2 + 12x - 30 \]

Now, we can identify \(A\), \(B\), and \(C\) in the standard polynomial form \(Ax^3 + Bx^2 + Cx + D\):

  • \(A = 8\)
  • \(B = -13\)
  • \(C = 12\)
  • The constant term \(D = -30\)

So, the values of \(A\), \(B\), and \(C\) are:

\[ A = 8, \quad B = -13, \quad C = 12 \]