√2 X^2-2X-√2=0
2X^2-2√2X-2=0
X^2-√2X-1=0
X^2-√2X+2/4-2/4-1=0
(X-√2/2)^2-6/4=0
(X-√2/2-√6/2)(X-√2/2+√6/2)=0
X=√2/2+√6/2或X=√2/2-√6/2
√2x^2-2x-√2=0
x^2-√2x-1=0
△=(√2)^2+4=6
x1,2=(√2±√6)/(2*1)
x1=(√2+√6)/2
x1=(√2-√6)/2
√2x²-2x-√2=0
a=√2 b=-2 c=-√2
b²-4ac=12
所以
x=[2±2√3]/(2√2)
=(√2±√6)/2
无解