If the two circles, `x^2+y^2+2g_1x+2 f_1y=0` & `x^2+y^2+2g_2x+2f_2y=0` touch each other then (1)`f_1g_1=f_2g_2` (2)`(f_1)/(g_1) = (f_2)/(g_2)` (3) `f_1f_2=g_1g_2` (4) none of these

If the two circles,x^(2)+y^(2)+2g_(1)x+2f_(1)y=0delta x^(2)+y^(2)+2g_(2)x+2f_(2)y=0 touch each other then (1)f_(1)g_(1)=f_(2)g_(2)(2)(f_(1))/(g_(1))=(f_(2))/(g_(2))(3)f_(1)f_(2)=g_(1)g_(2)(4) none of these

If two circle x^(2)+y^(2)+2gx +2fy=0 and x^(2)+y^(2)+2g'x+2f'y=0 touch each other then f'g =fg'.

If circles x^(2) + y^(2) + 2g_(1)x + 2f_(1)y = 0 and x^(2) + y^(2) + 2g_(2)x + 2f_(2)y = 0 touch each other, then

If circles x^(2) + y^(2) + 2g_(1)x + 2f_(1)y = 0 and x^(2) + y^(2) + 2g_(2)x + 2f_(2)y = 0 touch each other, then

Show that the condition that the circle x^2+y^2+2g_1x+2f_1y+c_1=0 bisects the circumference of the circle x^2+y^2+2g_2x+2f_2y+c_2=0 is 2(g_1-g_2)g_2+2(f_1-f_2)f_2=c_1-c_2