Final answer:
The expression provided by the student contains typos and cannot be accurately evaluated. For accurate evaluation, a clearer expression is needed, respecting the order of operations and understanding of positive and negative number operations.
Step-by-step explanation:
The question appears to be asking for the evaluation of a mathematical expression, but unfortunately, the expression provided is unclear and potentially contains typos. If the student can provide a clearer version of the expression, it can be evaluated step by step, taking into account the order of operations, which requires that calculations be performed in the following order: parenthesis, exponents, multiplication and division (from left to right), addition and subtraction (from left to right).
For example, if the student is asking to evaluate an expression like 3·2⁻¹(−10)−3 12, which seems to be a possible interpretation of the question, we would first handle the parenthesis and exponents, then multiplication and division, followed by addition and subtraction.
To clarify the role of a negative sign in operations: when combining a positive and a negative number, you subtract the smaller number from the larger one and take the sign of the larger number. For example, 5 - (+3) = 5 - 3 = 2, and 2 - (-6) = 2 + 6 = 8.
Regarding exponents, when dividing terms with the same base, subtract the exponents. For instance, if dividing 2.56 × 10⁻38 by 5 × 10⁻21, the calculation would be (5.12 ÷ 5) × 10⁻38-(-21) = 1.024 × 10⁻18.