Question

数学题配方题

高分求5至10道关于配方的因式分解的题，要有详细的解答过程和答案。好的话还可以追加。

Answer 1

配方：
1. X²+2X+3=(x+1)²+2

2. X²+2X-5=(x+1)²-6

3. 3X²+5X+4=3(x²-5x/烂困手3)²+4=3(x-5/尺誉6)²-3(5/6)²+4=3(x-5/6)²+23/12

4. 3X²+9X+4=3(x²+3x)+4=3(x+3/饥嫌2)²-3*3(3/2)²+4=3(x+3/2)²-11/4

5.2y-2y²-1
=-2y^2+2y-1
=-2(y^2-y)-1
=-2(y-1/2)^2+1/2-1
=-2(y-1/2)^2-1/2

Answer 2

配方： 1. X2-2X-8=X2-2X+1-9
=(x-1)2-32
= [(x-1)+3][(x-1)-3]
= (x+2)(x-4)
2. X2+4X-5=X2+4X+4-9
=(x+2)2-32
= [(x+2)+3][(x+2)-3]
= (x+5)(x-1)

3. X2+6X+8
= （X2+6X+9）-1
=(x+3)2-12
= [(x+3)+1][(x+3)-1]
= (x+4)(x+2)
4
a2-4a-12
=a2-4a+4-16
=（a-2）2-16
=（a-2）2-42
=（绝森神a-2-4)*（并亏春宽a-2+4）
=(a-6)*(a+2)
5
2 y2- y -1
=(y2- y)+( y2- 1)
= y( y- 1)+ ( y+1) ( y- 1)
= ( y- 1)[ y+( y+1)]
= ( y- 1)( 2y+1)