Respuesta :

Answer

given,

a) x-1=0

adding both side with 1

   x = 1

b) x + 1 =0

subtracting both side by 1

    x = -1

c) x²- 1 =0

   x² = 1

taking square root

   x = √1

   x = 1

d) x²+ 1 =0

   x² = -1

taking square root

   x = √-1

   x = i (iota)