因式分解問題:(中學)
回答 (3)
2006-10-18 8:28 am
✔ 最佳答案
4x^2 - 36z^2 - 28xy + 49y^2= 4x^2 - 28xy + 49y^2 -36z^2
= (2x - 7y)^2 - 36z^2 --- By (a^2-2ab+b^2) = (a+b)^2
= (2x - 7y)^2 - (6z)^2
= (2x-7y+6z)(2x-7y-6z) --- By a^2-b^2 = (a+b)(a-b)
參考: myself
2006-10-18 8:34 am
4x^2-36z^2-28xy+49y^2
= 4x^2 - 28xy + 49y^2 -36z^2
= (2x) ^2 – 2 (2x) (7y) + (7y) ^2 – 36z^2
= (2x – 7y) ^2 – (6z) ^2
= [(2x – 7y) + 6z] [(2x – 7y) - 6z]
= (2x – 7y + 6z) (2x – 7y - 6z)
= 4x^2 - 28xy + 49y^2 -36z^2
= (2x) ^2 – 2 (2x) (7y) + (7y) ^2 – 36z^2
= (2x – 7y) ^2 – (6z) ^2
= [(2x – 7y) + 6z] [(2x – 7y) - 6z]
= (2x – 7y + 6z) (2x – 7y - 6z)
參考: myself
2006-10-18 8:29 am
4x^2 - 36z^2 - 28xy + 49y^2
= 4x^2 - 28xy + 49y^2 - 36z^2
= ( 2x - 7 )^2 - 36z^2
= [( 2x - 7 ) + 6z ][( 2x - 7 ) - 6z ]
= ( 2x - 7 + 6z )( 2x - 7 - 6z )
= 4x^2 - 28xy + 49y^2 - 36z^2
= ( 2x - 7 )^2 - 36z^2
= [( 2x - 7 ) + 6z ][( 2x - 7 ) - 6z ]
= ( 2x - 7 + 6z )( 2x - 7 - 6z )
參考: Myself
收錄日期: 2021-04-12 19:04:53
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