Step1:∵4kx2-4kx+k+1=0,
由韦达定理可知,
x1x2=(k+1)/4k,x1+x2=-(-4k/4k)=1
∴(2x1-x2)(x1-2x2)=2(x1+x2)^2-9x1x2(“^2”是“平方”的意思)
=2-9(k+1)/4k
Step2:令2-9(k+1)/4k=3/2,
解得 k=- 9/2
P.S.介不介意好歹给些悬赏分?
Step1:∵4kx2-4kx+k+1=0,
由韦达定理可知,
x1x2=(k+1)/4k,x1+x2=-(-4k/4k)=1
∴(2x1-x2)(x1-2x2)=2(x1+x2)^2-9x1x2(“^2”是“平方”的意思)
=2-9(k+1)/4k
Step2:令2-9(k+1)/4k=3/2,
解得 k=- 9/2
P.S.介不介意好歹给些悬赏分?