MATHS (簡易多項式的因式分解)

1. x^2 - 3x - 4
=(x-4)(x+1)
p.12
1. 3 - 4x + x^2
=(x-3)(x-1)
2. 4x - x^2 +5
=-(x^2-4x-5)
=-(x-5)(x+1)
p.11
1. 5x^2 + 9x - 2
=(5x-1)(x+2)
2. 6x^2 - x - 1
=(2x-1)(3x+1)
p.14
1. -10 + 7c - c^2
=-(c^2-7c+10)
=-(c-2)(c-5)
2. 48x^2 - 1 +2x
=(8x-1)(6x+1)
3. 20 - 6x^2 + 7x
=-(6x^2-7x-20)
=-(2x-5)(3x+4)
4. 12 - 15x^2 - 11x
=-(15x^2+11x-12)
=-(3x+4)(5x-3)
5. -xy + 2y^2 - 3x^2
=(2y-3x)(x+y)

p.11
1. x2-3x-4
=(x-4)(x+1)

p.12
1. 3-4x+x2
=x2-4x+3
=(x-3)(x-1)
2. 4x-x2+5
=-(x2-4x-5)
=-(x-5)(x+1)

p.11
1.5x2+9x-2
=(5x-1)(x+2)
2. 6x2-x-1
=(2x-1)(3x+1)

p.14
1. -10 + 7c - c2
=-(c2-7c+10)
=-(c-2)(c-5)

2. 48x2- 1+2x
=48x2+2x-1
=(6x+1)(8x-1)

3.20-6x2+7x
=-(6x2-7x-20)
=-(3x+4)(2x-5)

4.12-15x2-11x
=-(15x2+11x-12)
=-(3x+4)(5x-3)

5.-xy+2y2-3x2
=-(3x2+xy-2y2)
=(3x-2)(x+1)