Mathematic Problems
x+x2-1+x-x2-1=2x+1
x+x2-1+x-x2-1=2x+1 x21x1
x+x2-1+x-x2-12=2x+12
x+x2-12+2x+x2-1x-x2-1+x-x2-12=2x+1
x+x2-1+2x+x2-1x-x2-1+x-x2-1=2x+1
2x+2x2-x2-12=2x+1
2x+2x2-x2-1=2x+1
2x+2x2-x2+1=2x+1
2x+21=2x+1
2x+1=2x+1
x+1=x+1
x=x xR
xRx1
x1
x1