Answer:
D. The possible degrees are 0, 1, and 2 because it cannot be higher than the degree of either P or Q but it can be less depending on which terms cancel.
Step-by-step explanation:
The possible degrees are 0, 1, and 2. Let's explain why by assuming the following is given:
P = 6x² - 3x - 2
Q = 3x² + 2x - 6
Let R = P - Q
Thus:
(6x² - 3x - 2) - (3x² + 2x - 6)
Open parentheses by distributing the factor of -1
6x² - 3x - 2 - 3x² - 2x + 6
Add like terms together
6x² - 3x² - 3x - 2x - 2 + 6
R = 3x² - 5x + 4
The leading term of R has a degree of 2. Therefore, the difference of two degree-2 polynomial functions P and Q can give us a a polynomial function of R with a degree of 2.
Also, let us assume the following:
P = 4x² + 4x - 3
Q = 4x² + x - 8
Let R = P - Q
R = (4x² + 4x - 3) - (4x² + x - 8)
R = 4x² + 4x - 3 - 4x² - x + 8
Collect like terms
R = 4x² - 4x² + 4x - x - 3 + 8
R = 4x + 5 (4x² cancels 4x²)
The leading term of R has a degree of 1. Therefore, the difference of two degree-2 polynomial functions P and Q can give us a a polynomial function of R with a degree of 1.
Also, let us assume the following:
P = x² + 2x - 3
Q = x² + 2x - 8
Let R = P - Q
R = (x² + 2x - 3) - (x² + 2x - 8)
R = x² + 2x - 3 - x² - 2x + 8
Collect like terms
R = x² - x² + 2x - 2x - 3 + 8
R = 5 (x² cancels x², and 2x cancels 2x)
The polynomial R has a degree of 0. Therefore, the difference of two degree-2 polynomial functions P and Q can give us a a polynomial function of R with a degree of 0.
Therefore we can conclude that:
D. The possible degrees are 0, 1, and 2 because it cannot be higher than the degree of either P or Q but it can be less depending on which terms cancel.
