Quadruple jump controversy maneuver in figure skating. "When it comes to a quadruple jump- it is quite simple really. If no one except for the one Russian skater is able to perform it, you need to make believe that this jump does not exist at all." TV commentators and experts saw Plushenko's "saving power" in managing to land a seemingly off-axis triple Axel as a testament to what real mastery is all about, as few would have been able to save it. "This is exactly what determines the great skill of a figure skater – the ability to save a jump when needed,
Quadruple product Quadruple product In mathematics, the quadruple product is a product of four vectors in three-dimensional Euclidean space. The name "quadruple product" is used for two different products, the scalar-valued scalar quadruple product and the vector-valued vector quadruple product or vector product of four vectors . The scalar quadruple product is defined as the dot product of two cross products: where a, b, c, d are vectors in three-dimensional Euclidean space. It can be evaluated using the identity: or using the determinant: The vector quadruple product is defined as the cross product of two cross products: where a, b, c, d