Browse Questions

# The set of all real values of $\;\lambda\;$ for which exactly two common tangents can be drawn to the circles $\;x^{2}+y^{2}-4x-4y+6=0\;$ and $\;x^{2}+y^{2}-10x-10y+\lambda=0\;$ is the interval :

$(a)\;(12 , 32)\qquad(b)\;(18 , 42)\qquad(c)\;(12 , 24)\qquad(d)\;(18 , 48)$