The radius of a circle is c r=AC= 1.
(x- 1)? +(y- 1)? = 1 ?
In circle x? +y? =r? On, the tangent of passing point (xo, yo) is xxo+yyo=r?
Point P (2,3) is the tangent L of circle C, 2x+3y = 1.
y=-2x/3+ 1/3
2
Circle c1:x 2+y 2-2mx+4y+m 2-5 = 0, (x-m)? +(y+2)? =9
Circle C2: x 2+y 2+2x-2my+m 2-3 = 0, (x+ 1)? +(y-m)? =4
Two circles are circumscribed, and the center distance is equal to the sum of radii; √[(m- 1)? +(m-2)? ]=5
m =-2.5
Contains two circles, the center distance is equal to the radius difference; √[(m- 1)? +(m-2)? ]= 1
m= 1,2