Richard K. Guy
Richard Guy loved math. He looked for patterns in numbers. He also loved playing games. Math helps us understand the world. He worked hard for many years. Do you like math too?
Early Reader · Change the reading level on the articleMathematics articles — Page 26
Explore the ideas and history behind numbers, shapes, patterns and mathematical thinking. Choose an article below; its reading controls let you move between the available levels.
1,419 public articles · Page 26 of 30
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Riemann integral
Imagine a wiggly line on a page. We want to find the space under it. We can use many tiny boxes to fill the space. We add the boxes up to find the size. This helps us measure tricky shapes. Can you find shapes under…
Early Reader · Change the reading level on the articleRiemann sphere
Imagine a flat map. Now, wrap it around a ball. This ball helps us see big numbers. It can even show a number that never ends. It is like a round world for math. Can you find a ball?
Early Reader · Change the reading level on the articleRiemann sum
We can use small boxes to find a size. We fill a shape with many boxes. Each box is a little bit smaller. This helps us find the right size. It is a fun way to measure. Can you find shapes in your room?
Early Reader · Change the reading level on the articleRiemann zeta function
Math can find hidden patterns. It helps us find special numbers. These numbers are like keys. They help us understand how numbers work. We use math to solve big puzzles. Do you like puzzles?
Early Reader · Change the reading level on the articleRight triangle
A right triangle has a special corner. This corner looks like the corner of a book. Two sides meet in a straight way. One side is very long. It is the side across from the corner. You can find these shapes…
Early Reader · Change the reading level on the articleRobert Aumann
Robert is a math expert. He studies how people work together. He also looks at how people fight. His work helps us understand the world. He won a very big prize. Do you like math?
Early Reader · Change the reading level on the articleRobert Langlands
Robert is a math expert. He finds ways to link ideas. He helps us see how things fit. This work is very big. It helps us learn more. Do you like math?
Early Reader · Change the reading level on the articleRod (unit)
A rod is a way to measure. It helps people see how long land is. It is used to measure big fields. This helps people know what they own. It is a very old tool. Can you find something long to measure with?
Early Reader · Change the reading level on the articleRoger Penrose
Roger Penrose loves math. He looks at the stars. He thinks about black holes. He also draws strange shapes. These shapes look impossible. He writes books about the world. Do you like math too?
Early Reader · Change the reading level on the articleRoot-finding algorithm
We can hunt for a special number. This number makes a math rule work. It is like finding a hidden spot. We make a guess first. Then we get closer and closer. It is like a game. Can you find it?
Early Reader · Change the reading level on the articleRoot of unity
Some numbers make a one. They work in a special way. They can form a shape. These shapes look like a ring. They help us find patterns. Do you like shapes?
Early Reader · Change the reading level on the articleRotation (mathematics)
A turn is a kind of move. You can turn things in a circle. One spot stays in the same place. This spot is the center. It can be a small turn or a big turn. It helps us move things. Can you spin in a circle?
Early Reader · Change the reading level on the articleRotations in 4-dimensional Euclidean space
Things can spin in many ways. We see things spin in our world. Some things spin in a new way. This is a special kind of spin. It happens in a big space. Can you imagine a new spin?
Early Reader · Change the reading level on the articleRule of inference
Rules help us think well. They show us how to find new facts. If one thing is true, the next part must be true too. This helps us solve puzzles. It helps us learn. Do you like to solve puzzles?
Early Reader · Change the reading level on the articleRule of product
You can count many ways to pick things. Pick a crust for your pizza. Then pick a topping too. This helps you see all the ways. It makes counting easy for us. Can you find all the ways? It is fun to count!
Early Reader · Change the reading level on the articleRunge–Kutta methods
Math can help us guess the future. We can use math to see how things change. It helps us find the right path. This is very useful for us. Do you like math puzzles?
Early Reader · Change the reading level on the articleSaddle point
Some shapes curve in two ways. It goes up in one way. It goes down in another way. It looks like a seat for a horse. You can see this shape on a snack chip! Can you find a shape like this?
Early Reader · Change the reading level on the articleSample mean and covariance
We can find a middle number. We look at a small group of things. This helps us learn about everything. It is a smart way to guess. Do you like to find patterns?
Early Reader · Change the reading level on the articleSample size determination
We want to learn about a big group. We cannot ask everyone. We pick a small group to help. A bigger group helps us be sure. It gives us better answers. How many people would you ask?
Early Reader · Change the reading level on the articleSample space
Think about what can happen. If you flip a coin, it can be heads or tails. These are the two choices. You can list all the choices first. Then you can guess what will happen. What could happen next?
Early Reader · Change the reading level on the articleSampling error
Sometimes we look at a small group. We want to know about a big group. The small group is not the same. It might be a little bit off. This is a tiny mistake. Can you find a small group?
Early Reader · Change the reading level on the articleSamuel Eilenberg
Some people love math. Samuel Eilenberg was one. He found new ways to see shapes. He also liked art from far away. He gave his art to a big museum. Do you like math or art?
Early Reader · Change the reading level on the articleSaunders Mac Lane
Saunders Mac Lane loved math. He looked for patterns. He found new ways to see math. This helped many people learn. He wrote books to help us. Do you like math too?
Early Reader · Change the reading level on the articleScalar (mathematics)
Numbers tell us how much of something we have. A number can make things grow. It can also make things small. We use numbers to change how long things are. It helps us measure things. Do you like to count things?
Early Reader · Change the reading level on the articleScalar multiplication
You can make things longer. Imagine an arrow. You can stretch it out. You can also make it small. It stays in the same way. This helps us change sizes. Do you like to build big things?
Early Reader · Change the reading level on the articleScaling (geometry)
You can make things big or small. You can grow a picture. You can also shrink a toy car. It keeps the same shape. This helps us see things clearly. Do you like big or small things?
Early Reader · Change the reading level on the articleScatter plot
You can use dots to show facts. Each dot is a new piece of info. We put dots on a page. They make a shape or a line. This helps us see how things work. It is like a map of ideas. Can you see the pattern?
Early Reader · Change the reading level on the articleSecant method
We can find a secret spot on a line. We use two points to help us. We draw a line to guess where to go. We do this many times. It helps us get closer and closer. Can you find the spot too?
Early Reader · Change the reading level on the articleSecond derivative
We can see how things change. A car can speed up or slow down. This tells us how the speed changes. It helps us see curves in a line. Do you like to watch things move?
Early Reader · Change the reading level on the articleSeki Takakazu
A man named Seki loved numbers. He lived in Japan a long time ago. He found new ways to use math. This helped people study the stars. He even found a special number for circles. His work was very smart. Do you like…
Early Reader · Change the reading level on the articleSemiprime
Some numbers come from two small numbers. We can make them by joining groups. These numbers are special and fun. They help us hide secret notes. We use them to keep things safe. Can you find two numbers to join?
Early Reader · Change the reading level on the articleSeparation of variables
Math can help us solve puzzles. We can split one big problem into two small ones. This makes the math easier to do. It helps us learn about how things grow. It is a smart way to work. Can you find patterns in your room?
Early Reader · Change the reading level on the articleSequence space
You can make long lists of numbers. These lists can go on and on. We can group these lists together. They help us find patterns. We use them to solve puzzles. Do you like making lists?
Early Reader · Change the reading level on the articleSerge Lang
Serge Lang loved math. He studied numbers and shapes. He wrote many books to help others learn. He was also a teacher at a big school. He liked to share what he knew. Do you like to learn new things?
Early Reader · Change the reading level on the articleSeries expansion
We can use many small parts to make a big thing. These parts work together. They can help us find an answer. It is like building with blocks. We can use a few blocks or many blocks. It helps us see things better. Can…
Early Reader · Change the reading level on the articleSeven Bridges of Königsberg
A city had seven bridges. People wanted to walk them all. They wanted to cross each bridge just once. A man named Euler tried to find a way. He found it was not possible. Can you find a path like that?
Early Reader · Change the reading level on the articleSexagesimal
We use sixty to count time. One hour has sixty minutes. One minute has sixty seconds. This helps us share time fairly. It started a long time ago. Do you like to tell time?
Early Reader · Change the reading level on the articleShannon (unit)
We use bits to talk about data. A shannon is a way to measure it. It helps us know how much news we get. This helps us send things to friends. It is a very smart idea. Can you think of a way to send a message?
Early Reader · Change the reading level on the articleShear mapping
You can tilt a shape. It looks like it is sliding. A square can become a tilt. The size stays the same. It just looks different. Can you see the tilt?
Early Reader · Change the reading level on the articleSheffer stroke
We use rules to think. One rule is "not both." It means one thing is false. This rule helps computers work. It is in every computer. We use it every day. Do you like computers?
Early Reader · Change the reading level on the articleShigefumi Mori
Shigefumi Mori loves math. He looks at shapes. He found new ways to see them. He won a big prize for his work. He helps us learn more. Do you like shapes too?
Early Reader · Change the reading level on the articleShiing-Shen Chern
A man named Chern loved shapes. He studied how they work. He was a great math teacher. His ideas help us learn about the world. He even wrote poems. Do you like shapes too?
Early Reader · Change the reading level on the articleShing-Tung Yau
Shing-Tung Yau loves math. He solves big puzzles with shapes. He won a very special prize. He helps many people learn math too. He works at a big school. Do you like math?
Early Reader · Change the reading level on the articleShooting method
Imagine you are aiming a big cannon. You want to hit a spot far away. You try one way, but you miss. You change your aim and try again. You keep trying until you hit it! This helps us find the right path. Can you aim…
Early Reader · Change the reading level on the articleShortest path problem
You want to get somewhere fast. You look at a map. You find the best way to go. It might be a short road. It might be a quick way. This helps you find your way. Can you find the best path?
Early Reader · Change the reading level on the articleSierpiński triangle
This is a special shape. It looks like many small triangles. You can make it by taking away parts. You keep taking away small pieces. The pattern stays the same. It is very pretty to see. Can you find the small…
Early Reader · Change the reading level on the articleSieve of Eratosthenes
You can find special numbers. We use a list of numbers. We cross out the ones we do not need. This helps us find the special ones. It is like using a sieve. Can you find them too?
Early Reader · Change the reading level on the article