Question

Without actually calculating the cubes, find the value of 45^3 - 25^3 - 20^3URGENT!!!!

Answer 1

u can find this by the identity ,
                  ∵x+y+z=0
                  ∴x^3+y^3+z^3=3xyz
and,             45-25-20=0
                 ⇒(45)^3-(25)^3-(20)^3=3(45)(-25)(-20)
                 ∴ur answer is 67500
                          hope this will help u.