Find the smallest integer solution to the equation 1/x^2 + 1/y^2 = 1/z^2
Gravity on the Moon is about 1/6th that on the Earth. A
pole-vaulter 2 metres tall can clear a 5 metres pole on the Earth.
How high a pole could he clear on the Moon?
Prove that k.k! = (k+1)! - k! and sum the series 1.1! + 2.2! + 3.3!