then prove \frac{1}{a+b}+\frac{1}{b+c}+\frac{1}{c+a}+\frac{1}{2}\cdot\frac{abc}{ab+bc+ca}\ge \frac{5}{3}.$$
and 
Prove that
Let 
Prove that
Let 
Prove that
Let 
Prove that
Y by
In a right-angled triangle, the sum 
of the sides enclosing the right angle equals 
while the length of the altitude 
on the hypotenuse 
is 
. Determine the length of the hypotenuse.
of the sides enclosing the right angle equals 
while the length of the altitude 
on the hypotenuse 
is 
. Determine the length of the hypotenuse.
