Cube root solution expressions involve the real cube root of a real number, while if all three solutions are real numbers then they may be expressed in terms of the complex cube root of a complex number. Quartic equations can also be solved in terms of cube roots and square roots. The calculation of cube roots can be to traced back to Babylonian mathematicians from as early as 1800 BCE. In the fourth century BCE Plato posed the problem of doubling the cube, which required a compass-and-straightedge construction of the edge of a cube with twice the volume of a given cube;
Curiosity: What's Inside the Cube? messages. Players tapped the cubelets to dig through the surface of each layer and reveal the next layer below. The goal was to reach the center and to discover what was inside the cube. Each layer, which had a distinct look or design, contained a clue as to what was in the centre of the cube. Each cubelet destroyed by a player awarded them coins. Coins could be spent on tools that temporarily enhanced the player's abilities, such as picks ranging from iron to steel to diamond that increased the number of cubelets destroyed with each tap, or firecrackers that