If `(lz_2)/(mz_1)` is purely imaginary number then `|(lambda z_1+muz_2)/(lambdaz_1-muz_2)|` is equal to

If (z-1)/(z+1) is purely imaginary then

if (5z_(2))/(7z_(1)) is purely imaginary number then |(2z_(1)+3z_(2))/(2z_(1)-3z_(2))| is equal to

if (5z_2)/(7z_1) is purely imaginary number then |(2z_1+3z_2)/(2z_1-3z_2) | is equal to

If (2z_(1))/(3z_(2)) is purely imaginary number, then |(z_(1)-z_(2))/(z_(1)+z_(2))|^(4) is equal to

If (2z_(1))/(3z_(2)) is purely imaginary number, then |(z_(1)-z_(2))/(z_(1)+z_(2))|^(4) is equal to

If (2z_(1))/(3z_(2)) is purely , an imaginary number , then |(z_(1) - z_(2))/(z_(1) + z_(2))| is equal to

If (z-1)/(z+1) is purely imaginary, then |z|=