Final answer:
To write the given expression in standard form, distribute the negative sign across the second parentheses, combine like terms, which gives you '-6x³ - 8x² + 5x + 12' as the standard form of the expression.
Step-by-step explanation:
To write the expression (x³ - 3x² + 5x) - (7x³ + 5x² - 12) in standard form, you need to perform subtraction by distributing the negative sign to the terms inside the second set of parentheses and then combine like terms.
- Distribute the negative sign: x³ - 3x² + 5x - 7x³ - 5x² + 12.
- Combine like terms: (x³ - 7x³) + (-3x² - 5x²) + (5x) + (12).
- Simplify the expression: -6x³ - 8x² + 5x + 12.
So, the expression in standard form is -6x³ - 8x² + 5x + 12.