x^2-(2k-1)x+k^2-k+1/4=0怎么算?

问题描述:

x^2-(2k-1)x+k^2-k+1/4=0怎么算?

x^2-(2k-1)x+k^2-k+1/4=x^2--2(k-1/2)x+(k-1/2)^2=(x-(k-1/2))^2=0 所以x=k-1/2