the no of quadratic eq which r unchanged by squaring the roots is

A)2           b)4       c)6           d)8

vlet quadratic eqn be ax²+bx+c=0 and roots be d and e,then roots of ax²+bx+c are d² and e² now there are four cases

d²=d,e²=e, d²=e, e²=d

d(d-1)=0 hence we get d=0 or d=1

e(e-1)=0 hence we get e=0 and e=1

then eqn satisfying d²=e are 0 and 1 for d and e similarly for e²=d we get 0 and 1 as answer

hence pairs possible for roots are (0,0) (0,1) (1,0) (1,1)

hence answer is 4