Final answer:
Expressions D (if 'nun' means 'n squared') and F (if it's a typo and should be 'n squared') represent a quadratic relationship. The other expressions given do not demonstrate quadratic characteristics as they are either linear or not in standard notation.
Step-by-step explanation:
The student is asked to identify which expressions represent a quadratic relationship between the step number and the total number of dots in a pattern. A quadratic relationship is one in which the dependent variable is proportional to the square of the independent variable, which in this case is represented by n. Looking at the provided expressions:
- A (I2) - This does not appear to be in standard mathematical notation.
- B (2n) - This is a linear expression, not quadratic.
- C (non answer A) - This appears to be a typo or a formatting issue.
- D (nun) - If interpreted correctly as n times n which is n2, this is indeed a quadratic expression.
- E (n + 2) - This is a linear expression.
- F (n=2) - This is an equation, most likely a typo for the expression n2, which would be quadratic.
Based on the interpretations above, the expressions that represent a quadratic relationship are potentially D (nun) and F (n2), assuming F was meant to be n2 instead of n=2. It is important to confirm the correct notation for the expressions, especially those that contain typos or formatting issues.