how can you factor 27x∧(3)-64?

4 Answers

• 27x^3 - 64 =

  (3x)^3 - (4)^3

  Now apply this difference-of-cubes formula:

  a^3 - b^3 = (a-b)(a^2 + ab + b^2)

  This gives you (3x - 4)(9x^2 + 12x + 16)

  Somebody else gave (3x - 4)^3 as an answer, which is just plain wrong. You can't just distribute the exponent like that. Notice that if you let x=2, then (3x)^3 - (4)^3 = 6^3 - 4^3 = 152, but (3x-4)^3 = (6-4)^3 = 8.

  (EDIT: nevermind, they seem to have deleted it)

• 27x 3 64

• (3x)^3 - 4^3

  (3x-4)(9x^2+12x+16) using a^3 - b^3 = (a - b) (a^2 +ab+b^2)

• Booty