中三-把多項式分解為因式~高手入!!15點!

1) g²+10g+25
=g²+2(5g)+5²
=(g+5)²

2) 16a²+8a+1
=(4a)²+2(4a)(1)+1²
=(4a+1)²

3) 9s²-6s+1
=(3s)²-2(3s)(1)+1²
=(3s-1)²

4) 36-12a+a²
=a²-12a+36
=a²-12a+6²
=a²-2(6a)+6²
=(a-6)²

5) 25p²+60pq+36q²
=(5p)²+2(5p)(6q)+(6q)²
=(5p+6q)²

6) 8-40L+50L²
=50L²-40L+8
=2(25L²-20L+4)
=2[(5L)²-2(5L)(2)+2²]
=2(5L-2)²

7) 80R²+40RS+5S²
=5(16R²+8RS+S²)
=5[(4R)²+2(4R)(S)+S²]
=5(4R+S)²

1)
g² + 10g+25
=(g+5)^2

2)
16a² +8a + 1
=(4a+1)^2

3)
9s² - 6s + 1
=(3s-1)^2

4)
36-12a + a²
=(a-6)^2

5)
25p² +60pq +36q²
=(5p+6q)^2

6)
8- 40L +50L²
=2(4-20L+25L^2)
=2(5L-2)^2

7)
80R² + 40RS +5S²
=5(16R^2+8RS+S^2)
=5(4R+S)^2

中六學生咁既錯都可以犯？
笑死人咩

To : LeeSin ying

第6題及第7題出現了一個嚴重錯誤 !!!

6. 8- 40L +50L² 不等於 25L^2 - 20L + 4
應該是 8- 40L +50L² = 2(25L^2 - 20L + 4)
=2[(5L)^2 - 2(5L)(2) + (2)^2]
=2(5L - 2)^2

7. 如上題同一道理

1) g² + 10g +25
=g² +2(5)g+5²
=(g+5)²

2) 16a² +8a + 1
=(4a)²+2(1)(4a)+1²
=(4a+1)²

3) 9s² - 6s + 1
=(3s)² - 2(1)(3s) + 1²
=(3s-1)²

4) 36-12a + a²
=a² - 2(6)a+6²
=(a-6)²

5) 25p² +60pq +36q²
=(5p)²+2(5p)(6q)+(6q)²
=(5p+6q)²

6) 8- 40L +50L²
=25L² - 20L+4
=(5L)² - 2(2)(5L)+2²
=(5L-2)²

7) 80R² + 40RS +5S²
=16R²+8RS+S²
=(4R)²+2(4R)S+S²
=(4R+S)²