求值域y=x+(x^2-3x+2)^1/2

问题描述:

求值域y=x+(x^2-3x+2)^1/2

由y=x+√(x²-3x+2)得 √(x²-3x+2)=y-x≥0 两边平方,得(2y-3)x=y²-2,从而,y≠3/2,且x=(y²-2)/(2y-3).由y-x=y-(y²-2)/(2y-3)≥0,得 (y²-3y+2)/(2y-3)≥0,1≤y〈3/2或y≥2.当y≥2时,由x=...