(a)因式分解 16x^2 + 18x - 9
(b)由此,因式分解 16(6y^2 - 3)^2 + 18(6y^2 - 3) - 9
因式分解唔識.........
2009-01-13 6:45 am
回答 (2)
2009-01-13 7:13 am
✔ 最佳答案
a)16x2 + 18x - 9
= (2x + 3)(8x - 3)
b)
Let x = 6y2 - 3
16(6y2 - 3)2 + 18(6y2 - 3) - 9
= 16x2 + 18x - 9
= (2x + 3)(8x - 3)
= [2(6y2 - 3) + 3][8(6y2 - 3) - 3]
= (12y2 - 6 + 3)(48y2 - 24 - 3)
= (12y2 - 3)(48y2 - 27)
= 3(4y2 - 1)•3(16y2 - 9)
= 9[(2y)2 - 1][(4y)2 - (3)2]
= 9(2y + 1)(2y - 1)(2y + 3)(2y - 3)
=
2009-01-13 7:17 am
a)
16x^2+18x-9
= (8x-3)(2x+3)
b)
16(6y^2-3)+18(6y^2-3)-9
= (8(6y^2-3)-3)(2(6y^2-3)+3)
= (48y^2-27)(12y^2-3)
16x^2+18x-9
= (8x-3)(2x+3)
b)
16(6y^2-3)+18(6y^2-3)-9
= (8(6y^2-3)-3)(2(6y^2-3)+3)
= (48y^2-27)(12y^2-3)
參考: me
收錄日期: 2021-04-29 18:16:52
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