Question 19
Find the greatest and the least possible values of
$$\sqrt{4-a^2}+\sqrt{4-b^2}+\sqrt{4-c^2}$$
when a,b,c are strictly positive real numbers satisfying $a^2+b^2+c^2=6$.
$$\sqrt{4-a^2}+\sqrt{4-b^2}+\sqrt{4-c^2}$$
when a,b,c are strictly positive real numbers satisfying $a^2+b^2+c^2=6$.