There are 10 kinds of people

[Skyhawk]

those that know binary and those that don't.

Recently the band on my favorite watch broke, and I had to use a gift watch that tells the time in binary, 4 leds for hours and 6 leds for minutes. I don't like the watch because it is "clunky" and because you have to push a bottom to read the time (shades of the 1970's).

Well, I wore the watch to our FLL robotics team meeting. The boys asked about the strange watch I was wearing, and I told them it was a binary watch. To my surprise none of them knew about the binary number system. I would have thought that techo-savy 12 year olds would have it down pat!

This past weekend I happened to ask one of the boys (home schooled) who says that he has had algebra I if he knew about imaginary number. Again to my surprise the answer was no. I think 12 is a little young for algebra, but I would think that any algebra course would cover imaginary and complex numbers. What do you do if you are using the quadratic formula and the discriminant is negative? Punt, I guess!

[coriolis]

those that know binary and those that don't.

What do you do if you are using the quadratic formula and the discriminant is negative? Punt, I guess!

First of all, I "get" the title.

Secondly, I suppose that the problems that are given to the kids are hand picked to avoid that dilemma.

If I can remember back to my schooling, I was probably first introduced to imaginary numbers in a 9th or 10th grade algebra course. They are probably not taught anymore if they are not on the standard tests designed to measure the schools and the teachers more than the students. (Don't get me started on that one)

In our class we didn't do much with imaginary numbers, but I learned that imaginary numbers exist.......or do they?

[george_r_1961]

those that know binary and those that don't.

What do you do if you are using the quadratic formula and the discriminant is negative? Punt, I guess!

First of all, I "get" the title.

Secondly, I suppose that the problems that are given to the kids are hand picked to avoid that dilemma.

If I can remember back to my schooling, I was probably first introduced to imaginary numbers in a 9th or 10th grade algebra course. They are probably not taught anymore if they are not on the standard tests designed to measure the schools and the teachers more than the students. (Don't get me started on that one)

In our class we didn't do much with imaginary numbers, but I learned that imaginary numbers exist.......or do they?

I learned about imaginary numbers in college. Cant remember a lot about them though.

[brunota2003]

Imaginary Numbers...ah yes, the 9i + 4x... we learned about them about 3 weeks ago...quite simple little buggers IMHO...I'm in 11th grade Algebra II

[JonathanBelles]

i was not taught imaginary numbers until algebra 2 in 10th grade

[Skyhawk]

Back when I was in school we started algebra in the 9th grade. I know that we were using the quadratic formula in the 9th grade because I remember that we had to be able to derive it by completing the square. I can't remember what year in school we started using complex numbers because I had already learned them myself using a little book that had all sorts of interesting mathematical facts and puzzles and other curiosities. Unfortunately unless one goes on to study a physical science or engineering the math learned in high school goes unused and is soon forgotten.

[coriolis]

I do engineering, and the math I use more than anything else is geometry. I still use those classic wordlets: "cah" (cosine = adjacent/hypotenuse), "soh" (sine=opposite/hypotenuse) and "toa" (tangent = opposite/adjacent). It's funny that they didn't teach these in the "new math." I found these on my own in an old book of my parents. They were teachers and had stuff from the 'old days' when teaching was by rote.

Forget about the calculus, differential equations, linear algebra (ugh, I think that was invented to punish people), statistics, matricies, etc. I use Excel as my calculator, and everything else is either published charts and graphs, or computer models.

It's still important to understand the physics and the mechanics, but all the math used to derive the equations, and even the equations themselves are long forgotten.

[senorpepr]

If an imaginary number exists in a math question with no one to solve it, then does it really exist?

[azsnowman]

2+2=6.....right?

[wxmann_91]

Uh...interesting title and post Welcome to the board.

I first heard of imaginary numbers in my Algebra 1-2 class in 7th grade. Did not formally learn them until last year.

Our schools are a bit slow on the math part - so yeah, most 12 yr olds would not know about imaginary numbers.

[Stephanie]

Imaginary numbers??? If it's like the algebraic equation above 9x+4i=y, then yes I know of them but I don't remember them being called that.

I did well with math, but I need to know what, how and why I would use a certain formula or equation. Everything was pretty much memorized and then forgotten. I would freeze in tests as well.

Sadistics is interesting, but then again, I need to see how it relates to something I am already familiar with and what the benefit is. Like Ed said, it's the good old Excel spreadsheets and charts for me. I've ne

[Skyhawk]

I do engineering, and the math I use more than anything else is geometry. I still use those classic wordlets: "cah" (cosine = adjacent/hypotenuse), "soh" (sine=opposite/hypotenuse) and "toa" (tangent = opposite/adjacent). It's funny that they didn't teach these in the "new math." I found these on my own in an old book of my parents. They were teachers and had stuff from the 'old days' when teaching was by rote.

Forget about the calculus, differential equations, linear algebra (ugh, I think that was invented to punish people), statistics, matricies, etc. I use Excel as my calculator, and everything else is either published charts and graphs, or computer models.

It's still important to understand the physics and the mechanics, but all the math used to derive the equations, and even the equations themselves are long forgotten.

Actually it depends on what kind of engineering you are doing and at what level. Complex numbers and trigonometry are related by Euler's formula http://en.wikipedia.org/wiki/Euler%27s_formula
and are much used by electrical engineers working with AC circuits, mechanical and aerospace engineers working with vibrations and control system engineers designing control algorithms.

I've earned my living for more that 30 years doing mathematical modelling (not weather or climate related). The standard tools are differential equations, both ordinary and partial, linear algebra, and numerical methods.

[coriolis]

It does depend. I'm a bottom-feeding civil Engineer, designing water supply and wastewater treatment facilities. I have to know a little about a lot of disciplines, such as chemistry, biology, structural analysis, fluid mechanics, geology, geography, sociology, mechanics of materials, statistics, machinery, law, economics, and even electronics and electric power. We look at the big picture, assemble a project, and get it constructed, while relying on the specialists in their respective fields. For the performance of various equipment we rely on the data published by the manufacturers to select it. On any given day I might be doing calculations on open channel flow, trying to convice a government regulator that our approach is sound, go out and observe construction, determine whether a municipality can afford a project, and then attend a public meeting in the evening.

We had an interesting problem in which some variable speed drives were malfunctioning because of transient currents in the utility power supply due to the effects of a nearby industry. We had to get some help from some experts, but ultimately we had to have an understandig of what was going on, to advise our client. I couldn't do that expert stuff day in and day out.

[Chacor]

I still use those classic wordlets: "cah" (cosine = adjacent/hypotenuse), "soh" (sine=opposite/hypotenuse) and "toa" (tangent = opposite/adjacent).

Students in secondary school here in Singapore are thought that too, but it's easy for many of us here in Singapore to remember that, because "Toa cah soh" in the Hokkien dialect means "Old lady with large legs"

[tomboudreau]

Imaginery numbers are numbers that you make up in your head, yes?

[coriolis]

I still use those classic wordlets: "cah" (cosine = adjacent/hypotenuse), "soh" (sine=opposite/hypotenuse) and "toa" (tangent = opposite/adjacent).

Students in secondary school here in Singapore are thought that too, but it's easy for many of us here in Singapore to remember that, because "Toa cah soh" in the Hokkien dialect means "Old lady with large legs"

Just as long as they're not talking about the teacher.

[kevin]

All numbers are complex numbers.