Introduction to Matrices: Types, Operations, and Properties
Gauss
Calculating the Inverse of a Matrix
Let A = (aij) be a square matrix of order n. To calculate the inverse of A, denoted as A-1, follow these steps:
Step 1: Building the Augmented Matrix
Build the n x 2n matrix M = (A | I), where A is in the left half of M and the identity matrix I is on the right.
Step 2: Gaussian Elimination
Keep the first row of M as it is. Below the first main diagonal element, a11 (which we’ll call the pivot), put zeros. Then operate as shown in the following example.
Example:
Key Terms in Statistics: Chapters 1, 2, 3, and 4
Chapter 4: Measures of Central Tendency and Skew
Measures of Central Tendency
Measures of central tendency represent the center of a distribution. The most common measures are:
- Mean: The average score, calculated by summing all scores and dividing by the total number of scores. Represented by ‘x̄’ for a sample and ‘μ’ for a population.
- Median: The middle score when scores are arranged in numerical order. If there’s an even number of scores, the median is the average of the two middle scores.
- Mode:
Understanding Slang, Register, and Synonymy in Language
Synonym and Register
Synonymy
A relationship of ‘sameness of meaning’ that may hold between two words.
Register
A style or way of speaking adopted by a group. The factors defining a register are:
- Degree of formality (“formal”/“polite” vs. “informal”/“intimate”)
- Profession or trade (linguists, academics, mountain climbers, miners)
- Channel (postcard, CB radio talk, e-mail, internet forums)
- Plus anything else which may create a community feeling among people.
Cross-Varietal Synonymy
The use
Read MoreUnderstanding the Cartesian Plane: Distance, Area, and Point Division
1.1 Location of Given Points in the Cartesian Plane
A plane, xy, formed by two perpendicular lines, is divided into four quadrants (I, II, III, IV).
The intersection point of these lines is called the origin (O), with coordinates (0, 0).
From the origin, you can observe positive and negative directions. Any point P in the plane is represented by ordered pairs (x, y). This system, used in analytic geometry, is known as the Cartesian plane.
To locate a point, distinguish the values of x and y. A positive
Read MoreProblem Solving in Mathematics Education: Approaches and Benefits
Problem Solving as Context (PSC)
For students to understand and make meaning out of the mathematics they learn in school, it should connect to the real world. Problem solving (PS) is the pedagogy that justifies teaching mathematics for real-life experience. To motivate students to realize the value of mathematics, the content connects to the real world, allowing them to gain PS experiences. PS motivates students, aiding their interest in specific areas and mathematical topics or algorithms by making
Read MoreMastering Modal Verbs: Can, Could, Must, Mustn’t, and More
Could – Could – Manage to – Managed to
Use
We use could as the past tense of can to talk about general abilities in the past.
- I could speak Italian really well when I lived in Venice.
- He could walk when he was only 8 months old.
- I could do the Times crossword ten years ago, but I can’t nowadays. I’m getting too old.
- I could run much faster when I was 20.
- I could read when I was only four.
- When I was young, I could run fast, but now I cannot.
- When I was in school, I could do a handstand, but now I’m too old.