2. 169-(m+7n)^2
3. (a-1)^2-(b-1)^2
4. (3x+y)^2-(z-2)^2
請指教
更新1:
第三題有分別既?? 邊個岩??
simple因式分解
回答 (4)
2007-09-10 1:43 am
1. (2+k)^2-9
=(2+k)^2--3^2
=(2+k+3)(2+k-3)
=(k+5)(k-1)
2.169-(m+7n)^2
=13^2--(m+7n)^2
=[13-(m+7n][13+(m+7n)]
=(13-m-7n)(13+m+7n)
3.(a-1)^2-(b-1)^2
=[(a-1)-(b-1)][(a-1)+(b-1)]
=(a-1-b+1)(a-1+b-1)
=(a-b)(a+b-2)
4.(3x+y)^2-(z-2)^2
=[(3x+y)-(z-2)][(3x+y+(z-2)]
=(3x+y-z+2)(3x+y+z-2)
=(2+k)^2--3^2
=(2+k+3)(2+k-3)
=(k+5)(k-1)
2.169-(m+7n)^2
=13^2--(m+7n)^2
=[13-(m+7n][13+(m+7n)]
=(13-m-7n)(13+m+7n)
3.(a-1)^2-(b-1)^2
=[(a-1)-(b-1)][(a-1)+(b-1)]
=(a-1-b+1)(a-1+b-1)
=(a-b)(a+b-2)
4.(3x+y)^2-(z-2)^2
=[(3x+y)-(z-2)][(3x+y+(z-2)]
=(3x+y-z+2)(3x+y+z-2)
參考: 自己
2007-09-10 1:34 am
1.(2+k)^2-9
= (2+k)^2-3^2
= [(2+k) +3] [ (2+k)-3]
=(k+5)(k-1)
2.169-(m+7n)^2
=13^2 - (m+7n)^2
=[13 + (m+7n)] [ 13 - (m+7n)]
=(13 + m + 7n)(13 - m - 7n)
3.(a-1)^2-(b-1)^2
=[(a-1) + (b-1)] [(a-1) - (b-1)]
=(a+b-2)(a-b)
4.(3x+y)^2-(z-2)^2
=[(3x+y) + (z-2)] [(3x+y) - (z-2)]
=(3x+y+z-2)(3x+y-z+2)
hope i can help u
= (2+k)^2-3^2
= [(2+k) +3] [ (2+k)-3]
=(k+5)(k-1)
2.169-(m+7n)^2
=13^2 - (m+7n)^2
=[13 + (m+7n)] [ 13 - (m+7n)]
=(13 + m + 7n)(13 - m - 7n)
3.(a-1)^2-(b-1)^2
=[(a-1) + (b-1)] [(a-1) - (b-1)]
=(a+b-2)(a-b)
4.(3x+y)^2-(z-2)^2
=[(3x+y) + (z-2)] [(3x+y) - (z-2)]
=(3x+y+z-2)(3x+y-z+2)
hope i can help u
2007-09-10 1:32 am
1, (2 + k)^2 - 9
= (2 + k)^2 - 3^2
= [(2+k) +3] [(2+k) - 3]
= (k+5) (k-1)
2, 169-(m+7n)^2
= 13^2 -(m+7n)^2
= [13-(m+7n)] [13+(m+7n)]
= (13-m-7n) (13+m+7n)
3, (a-1)^2-(b-1)^2
= [(a-1)-(b-1)] [(a-1)+(b-1)]
= (a-b)(a+b-2)
4, (3x+y)^2-(z-2)^2
= [(3x+y)-(z-2)] [(3x+y)+(z-2)]
= (3x+y-z+2) (3x+y+z-2)
= (2 + k)^2 - 3^2
= [(2+k) +3] [(2+k) - 3]
= (k+5) (k-1)
2, 169-(m+7n)^2
= 13^2 -(m+7n)^2
= [13-(m+7n)] [13+(m+7n)]
= (13-m-7n) (13+m+7n)
3, (a-1)^2-(b-1)^2
= [(a-1)-(b-1)] [(a-1)+(b-1)]
= (a-b)(a+b-2)
4, (3x+y)^2-(z-2)^2
= [(3x+y)-(z-2)] [(3x+y)+(z-2)]
= (3x+y-z+2) (3x+y+z-2)
參考: me
2007-09-10 1:30 am
1.
(2+k)^2-9
= (2+k)^2-3^2
= [(2+k) +3] [ (2+k)-3]
=(k+5)(k-1)
2.
169-(m+7n)^2
=13^2 - (m+7n)^2
=[13 + (m+7n)] [ 13 - (m+7n)]
=(13 + m + 7n)(13 - m - 7n)
3.
(a-1)^2-(b-1)^2
=[(a-1) + (b-1)] [(a-1) - (b-1)]
=(a+b-2)(a-b)
4.
(3x+y)^2-(z-2)^2
=[(3x+y) + (z-2)] [(3x+y) - (z-2)]
=(3x+y+z-2)(3x+y-z+2)
(2+k)^2-9
= (2+k)^2-3^2
= [(2+k) +3] [ (2+k)-3]
=(k+5)(k-1)
2.
169-(m+7n)^2
=13^2 - (m+7n)^2
=[13 + (m+7n)] [ 13 - (m+7n)]
=(13 + m + 7n)(13 - m - 7n)
3.
(a-1)^2-(b-1)^2
=[(a-1) + (b-1)] [(a-1) - (b-1)]
=(a+b-2)(a-b)
4.
(3x+y)^2-(z-2)^2
=[(3x+y) + (z-2)] [(3x+y) - (z-2)]
=(3x+y+z-2)(3x+y-z+2)
收錄日期: 2021-04-18 23:22:55
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