Saved Bookmarks
| 1. |
X minus y whole power of cube + y - Z whole power of cube + Z minus x whole power of cube |
|
Answer» 1. (a+B+c)^3 = a^3+b^3+c^3 + 3(a+b)(b+c)(a+c) 2. a^3+b^3+c^3 - 3 a b c = (a+b+c)(a^2+b^2+c^2 - a b - b c - a c) Also note that (a^2+b^2+c^2-ab-bc-ac)=1/2((a-b)^2+(b-c)^2+(a-c)^2) From equation 2. above, note that If a + b + c = 0, then a^3+b^3+c^3 - 3 a b c = 0 So a^3+b^3+c^3 = 3 a b c |
|