y=1-2x²-x⁴
0=1-2x-x⁴
0-1+2x²+x⁴=0
x⁴+2x²+0-1=0
t²+2t-1=0
t= -1+√2
t= -1-√2
x²= -1+√2
x²= -1-√2
x= -√-1+√2
x= -1+√2
x € R
x=√-1+√2
x1 = -√-1+√2
x2=√-1+√2
y=1-2x²-x⁴
0=1-2x-x⁴
0-1+2x²+x⁴=0
x⁴+2x²+0-1=0
t²+2t-1=0
t= -1+√2
t= -1-√2
x²= -1+√2
x²= -1-√2
x= -√-1+√2
x= -1+√2
x € R
x= -√-1+√2
x=√-1+√2
x1 = -√-1+√2
x2=√-1+√2