[15] Factorization

1. 2p-4q+8r
=2(p-2q+4r)
2. 6x^2 + 3xy - 9y
=3(2 x^2 +xy-3y)
3. k^3 - ck^2 + c^2 k
=k(k^2-ck+c^2)
4. 6c^4 + 2c^3 + 3cd
=c(6c^3+2c^2+3d)
5. -15y^4 - 5xy - 25y
=-5y(3y^3+x+5)
6. 2ab - 4bc + 8bd
=2(ab-2bc+4bd)
7. 3x^2 - 12xy - 9xy^2
=3x(x-4y-3y^2)
8. 14x^5 - 7x^4 + 21x^2
=7x^2(2x^3 - x^2 +3)
9. -12k^4 + 9k^3 - 15k^2
=9k^3-12k^4 - 15k^2
=3k^2(3k-4k^2 - 5)
10. 2x^3 y - x^2 y^2 + 4xy^3
=xy(3x^2-xy+4y^2)

2007-12-31 16:02:07 補充：
sorry,they should be6. 2ab - 4bc + 8bd=2b(a-2c+4d)10. 2x^3 y - x^2 y^2 + 4xy^3=xy(2x^2-xy+4y^2)

1. 2(p-2q+4r)
2. 3(2x^2 +xy - 3y) = 3(2x+3y)(x-y)
3. k (k^2 - ck + c^2)
4. c(6c^3+2c^2+3d)
5. -5y(3y^3+x+5)
6. 2b(a-2c+4d)
7. 3x(x-4y-3y^2)
8. 7x^2(2x^3-1x^2+3)
9. 3k^2(-4k^2+3k-5)
10. xy (2x^2-xy+4y^2)

hope i didn't do anyth wrong la...