Probability is a branch of mathematics used to study the rules and possible outcomes behind random events. In real life, we often run into situations where we need to predict results, and probability theory was created to solve these kinds of problems.

Basic concepts of 3D graphics: 3D graphics are solid figures in three-dimensional space that have length, width, and height, with volume and surface area.

Also called probability, it’s a core concept in math used to measure and describe how likely random events are to happen.

It’s a statistical chart in a Cartesian coordinate system that uses the distribution of sample data points (xi, yi) to visually show the relationship between two continuous variables.

When we look at an object from a certain direction, what we see is called a view of the object.

An upper bound refers to a number that is greater than or equal to all elements, while a lower bound is a number that is less than or equal to all elements. They are used to describe the boundary of a set or the range of a function's values.

Data collection, also known as data gathering, is the first step in the data processing and analysis workflow. It refers to the process of obtaining raw information from various sources using either manual or automated techniques. The sources are diverse, including databases, sensors, the internet, business systems, and public data sources, and the data collected can be either structured or unstructured. Common methods include surveys, manual entry, and automated techniques using web crawlers, API interfaces, or log systems. This process needs to follow core principles like accuracy, completeness, timeliness, consistency, and security. Data collection forms the foundation for decision-making and innovation in statistics, business intelligence, scientific research, and many other fields.

The square root is actually the inverse operation of squaring. If the square of a number equals a, then that number is the square root of a, denoted as ±√a.

Congruence generally refers to congruent figures. Congruent figures are two flat shapes that can completely overlap each other, meaning their shapes and sizes are exactly the same. They can match up perfectly after shifting, rotating, or flipping. As a special case, congruent triangles have all corresponding sides and angles exactly equal.

Balance equations are mainly used to describe the mathematical expressions of objects being in force balance or chemical reaction equilibrium. In mechanics, the most common case is when the resultant force and the resultant moment are zero. In physical mechanics, they are used to calculate unknown forces on structures; in chemistry, they describe the concentration relationships when a reaction reaches stability.