Question

|x+3|+(2x+y)^2=0,求4分之3x^2-(3y-4分之1x^2)+y的值

Answer 1

|x+3|≥0,(2x+y)^2≥0,

|x+3|+(2x+y)^2=0,

∴|x+3|=(2x+y)^2=0,

∴x=-3,y=-2x=6

∴3/4x²-(3y-1/4x²)+y = 3/4x²-3y+1/4x²+y = x²-2y = (-3)²-2*6 = -3