2012 · Q45
If x + y = 9 and xy = 8, then what is one of the values of (x^4 - y^4)?
Elementary MathematicsAlgebra
- A4025
- B4065
- C4095
- D4905
Explanation
x^4-y^4 = (x-y)(x+y)((x+y)^2-2xy) = (+-7)(9)(65) = +-4095.
If x + y = 9 and xy = 8, then what is one of the values of (x^4 - y^4)?
Explanation
x^4-y^4 = (x-y)(x+y)((x+y)^2-2xy) = (+-7)(9)(65) = +-4095.