因?yàn)閥=ax^2+bx+c的頂點(diǎn)坐標(biāo)是(-b/(2a),(4ac-b*b)/(4a))
所以該拋物線的頂點(diǎn)坐標(biāo)為：
((m-4)/2,(-m^2+16m-28)/4)
頂點(diǎn)在y軸上時(shí)：(m-4)/2=0,即m=4
頂點(diǎn)在x軸上時(shí)：(-m^2+16m-28)/4=0,即m=0或m=14
圖像過原點(diǎn)即過(0,0),代入方程得：
0+0+(2m-3)=0,即m=3/2
x^4+64
=x^4+64+16x^2-16x^2
=(x^2+8)-16x^2
=(x^2+8-4x)(x^2+8+4x)
x^2-4mx+8mn-4n^2
=(x+2n)(x-2n)+4m(2n-x)
=(x+2n-4m)(x-2n)
x^3-11x^2+31x-21
=(x³-1)-(11x³-31x+20)
=(x-1)(x²+x+1)-(11x-20)(x-1)
=(x-1)(x²+x+1-11x+20)
=(x-1)(x²-10x+21)
=(x-1)(x-3)(x-7)
x^3-4xy^2-2x^2y+8y^3
=x(x^2-4y^2)-2y(x^2-4y^2)
=(x-2y)(x^2-4y^2)
=(x-2y)(x+2y)(x-2y)
=(x+2y)(x-2y)^2