Find the equation of pair of tangents drawn to the circle x2 + y2 − 4x + 4y = 0 from the point (2, 2)
Given circle is,
x2 + y2 − 4x + 4y = 0,
and external point is (2, 2) we have to use the formula
SS1 = T2
[x2 + y2 − 4x + 4y] [4 + 4 − 8 + 8] = 2x + 2y − 2(x + 2) +2(y + 2)
8.[x2 + y2 − 4x + 4y] = 2y + 2y −4 + 4
4.[x2 + y2 − 4x + 4y] =4y
4x2 + 4y2 − 16x + 12y =0