x4

X4 is a term that can refer to different concepts depending on the context. In mathematics and related fields, x4 is commonly used to denote the fourth power of a variable x, written as x^4 in standard notation. Beyond pure math, X4 is also used as a model or product designation in various industries, including automotive and gaming.

In mathematics, x^4 is a monomial of degree four. It appears in polynomials, equations, and calculus, and its graph, y = x^4, is an even function that remains nonnegative for all real x and grows rapidly as |x| increases. The concept is fundamental in studying polynomial behavior, symmetry, and higher-degree integrals and derivatives.

In automotive naming, the BMW X4 is a mid-size luxury crossover SUV produced by BMW since 2014. It blends SUV practicality with a coupe-like roofline and sportier styling, positioned as a more dynamic alternative within BMW’s X lineup and sharing underpinnings with the X3.

In video gaming, X4: Foundations is a space trading and combat simulation game released in 2018 by Egosoft. It is the fourth title in the X series and emphasizes an open-ended, sandbox experience with dynamic economies, ship construction, and exploration across a large, procedurally generated galaxy. The game builds on the series' emphasis on player-driven commerce and faction interactions.