I don't get how to factor it if the variables are different.
any help is appreciated. thank you.
How do I factor the expression 56x^3 - 189y^3?
2008-12-08 8:50 am
回答 (3)
2008-12-08 10:49 am
✔ 最佳答案
a^3 - b^3 = (a - b)(a^2 + ab + b^2)56x^3 - 189y^3
= 7(8x^3 - 27y^3)
= 7[(2x)^3 - (3y)^3]
= 7[2x - 3y][(2x)^2 + 6xy + (3y)^2]
= 7[2x - 3y][4x^2 + 6xy + 9y^2]
2008-12-08 9:06 am
= 7(8x^3 - 27y^3) = 7(2x - 3y)(4x^4 + 6xy + 9y^2)
2008-12-08 9:05 am
=7(8x^3 - 27y^3)=7(2x-3y)(4x^2+6xy+9y^2)
收錄日期: 2021-05-01 11:36:07
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081208005054AAuXGE9