Question

Which products result in a sum or difference of cubes? Check all that apply.

A=(x – 4)(x2 + 4x – 16)
B=(x – 1)(x2 – x + 1)
C=(x – 1)(x2 + x + 1)
D=(x + 1)( + x – 1)
E=(x + 4)(x2 – 4x + 16)
F=(x + 4)(x2 + 4x + 16)


Sum of cubes:
(a + b)(a2 – ab + b2) = a3 + b3
Difference of cubes:
(a – b)(a2 + ab + b2) = a3 – b3

Answer 1

if you're from edge, the answer is C and E

Explanation:

Answer 2

C and E.
Formulas for sum of cubes and difference of cubes are:
a^3 + b^3 = (a + b) * (a^2 - a*b + b^2)
a^3 - b^3 = (a - b) * (a^2 + a*b + b^2)
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So, when you check each A, B, C, D, E, F, you can see that ONLY C and E satisfy the operators in both first and second parentheses.