题目应该是x²-5√2x+8=0用因式分解法x^2-5√2x+4√2*√2=0(x-4√2)(x-√2)=0 x1=4√2, x2=√2. x1=4√2,x2=√2用公式(-b±√b^2-4ac)/2ax={5√2±√[(5√2)^2-4*8]}/2=(5√2±√18)/2=(5√2±3√2)/2x1=4√2,...