# IntMath Newsletter: vision, wealth and slopes

By Murray Bourne, 28 Oct 2010

28 Oct 2010

In this Newsletter:

1. Math application: 20/20 vision and trigonometry

2. Math application: Statistics and wealth distribution

3. Math tip: The slope of the 3 main trigonometric curves

4. Friday math movies: Math education and cell animations

6. Final thought: Dealing with mistakes

Welcome to the hundreds of new people who have signed up for the IntMath Newsletter!

## 1. What does 20/20 vision mean?

**Suitable for: **Everyone. This article ties trigonometric concepts into something that's important for all of us - good vision.

We often hear the expression 20/20 vision. What do the 2 numbers mean? |

## 2. Singapore wealth - mean and median?

**Suitable for: **Everyone. The wealth distribution of a country affects its stability, so this is an important application of statistics.

When we have a distribution with a high mean but a low median, what does it look like? |

## 3. Explore the slope of the sin, cos and tan curves

**Suitable for: **Everyone. The slope of a straight line is easy - find vertical rise and divide by horizontal run. But what is the slope of a curve? This is an important concept and worth thinking about, even if you've never heard of calculus yet.

I broke this up into 3 separate articles to make it more digestible.

Use an interactive graph to explore how the slope of sine x changes as x changes. |

What is the value of the slope of the cosine curve? Use an interactive graph to investigate it. |

You can investigate the slope of the tan curve using an interactive graph. |

## 4. Friday math movies

**Suitable for: **Everyone.

## a. Arthur Benjamin's formula for changing math education

What math topic is most useful for people in their "real life"? Friday math movie: Arthur Benjamin's formula for changing math education |

## b. David Bolinsky animates a cell

Our bodies truly are beautiful and amazing. |

## 5. Final thought: Dealing with mistakes

Donald Trump had a very successful career in real estate until he ran into serious financial difficulties during the 1990s and basically went broke. He has since recovered and is now worth around US$2.6 billion.

The following quote by Trump applies to all math students!

"Make your mistakes work for you by learning from them."

Donald Trump

Until next time, enjoy whatever you learn.

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