因式分解2x^2-2x-8

问题描述:

因式分解2x^2-2x-8

2x^2-2x-8
=2(x^2-x-4)
=2[(x-1/2)^2-17/4]
=2(x-1/2+√17/2)(x-1/2-√17/2)
=2[x+(√17-1)/2][x-(√17+1)/2]