we know (a−b)2=a2+b2−2ab We have, ⇒x=2+21∕2 ⇒x−2=21∕2 On squaring both the sides, we get ⇒(x−2)2=(21∕2)2 ⇒(x−2)2=2 ⇒x2−4x+4=2 ⇒x2−4x+4−2=0 ⇒x2−4x+2=0 ⇒x2+2=4x On dividing by ' x ', we get ⇒x+
2
x
=4 Again squaring on both the sides, we get ⇒x2+
4
x2
+4=16 ⇒x2+
4
x2
=12 Again squaring on both the sides, we get ⇒x4+