Answer :

Let's simplify the given expression step-by-step:

The original expression is:
[tex]\[ (5x^2 + 2x + 6) + (x^3 - x - 2) - (7x^3 - 7x^2 - 5) \][/tex]

First, distribute the negative sign through the third term:
[tex]\[ (5x^2 + 2x + 6) + (x^3 - x - 2) - 7x^3 + 7x^2 + 5 \][/tex]

Next, combine like terms by combining the coefficients of the same power of [tex]\(x\)[/tex]:

For [tex]\(x^3\)[/tex]:
[tex]\[ x^3 - 7x^3 = -6x^3 \][/tex]

For [tex]\(x^2\)[/tex]:
[tex]\[ 5x^2 + 7x^2 = 12x^2 \][/tex]

For [tex]\(x\)[/tex]:
[tex]\[ 2x - x = x \][/tex]

For the constant terms:
[tex]\[ 6 - 2 + 5 = 9 \][/tex]

Now, combine all the simplified terms:
[tex]\[ -6x^3 + 12x^2 + x + 9 \][/tex]

So, the simplified expression is:
[tex]\[ -6x^3 + 12x^2 + x + 9 \][/tex]