When was the last time you used the quadratic formula?

[chomalungma]

Linked to the maths thread but a very specific example.

(-b +/-square root (b squared - (4ac) ) divided by 2a

Or do you just Google it?

what happens if b squared minus 4ac is negative

Aren't you into the realms of imaginary numbers then?

For O level Maths in 1980.

I used it last week but I am a Maths teacher.

I last used it a week ago...

… but only to tell y10 DD about it, and to get her to practice saying it, as you need to know it by heart for the new maths GCSE spec.

O Level maths in 1986. Maths wasn't my strong point anyway and I had the most useless, lazy maths teacher in existence (the kind of person who would never be allowed to teach these days - she didn't mark my exercise book once in 5 years of teaching). We didn't have the money for extra tutoring either. So I worked out that my best strategy for passing was to learn all the formulae and working-out methods off by heart, but make no effort to get the actual answer right. There were enough points available for just churning out the formula of quadratic equations etc and doing a few lines of working out. The strategy worked, I got a C at O level, probably got no or few actual answers correct at all. It was an example of everything that was wrong with the syllabus then. The emphasis at that age should have been more on functional maths for life skills. I do actually use limited maths and Excel charts for work now, but mostly percentage calculations.

teen - didn’t you always have to know it by heart? I certainly had to know all the formulas for O level. Was there a time you didn’t need to know it?

My DD1 did GCSEs under the old spec 4 years ago and I am 99% confident it was given as a formula at the start of her paper. It seems likely as she was given a load of formulae for Physics too which I think DD2 now has to learn.

Interesting. Mine did GCSEs a few years ago too. I had no idea they were given formulae. I just assumed they had to learn them!

Same as fuzzypuffling...o level maths in 1974!!

Do you think its normal to not remember anything you studied at Uni and haven't used for 30 years????

First year at university probably (you had to do it if you were doing a science).

I have solved quadratic equations since, but I prefer to use the "completing the square" method.

Actuary here. I've used it occasionally at work, can't remember what exactly, maybe back-solving for an interest rate or fitting a quadratic to some function.

I can remember, I can prove it, and if I really want a mental workout I sit down and try to remember how to find a formula for solving a cubic!

Do you think its normal to not remember anything you studied at Uni and haven't used for 30 years?

I hope so. I don't think I could do any of the university maths I did 30 years ago. I can remember the names of the units and that's about it. (Actually I'm not convinced I could pass A level maths now without a decent run up to it.)

GCSE maths exam 2008.

I'm in my fifth year of medical school and also did three years of biomedical science not need it once.

It probably came up, perhaps we were given the formula in the paper?
I never remember having to learn any for maths only in science.
I wouldn't know what the hell you're trying to work out with it nowadays or why, I doubt i could do a maths paper how as I cant even understand how they teach year 3 maths currently.

I can't remember ever even learning it, but then that sort of maths is like an alien language to me.

So I suppose the answer is never.

I am numerate and do use basic maths on a regular basis at work, but have never had the remotest use for things like this, or other crap like algebra.

At school

This morning. I was solving a simultaneous equation with quadratics to prove a relationship between two apparently unconnected equations. I ended up with a quadratic to solve.

At school

A couple of months ago to help dd with her homework. I had to google the method. Before that I hadn't used it since 1987.

Never used it in my life after Maths O-level in 1972. Didn't understand the point of it then and still don't.

Ditto in spades for simultaneous equations.

Total waste of my time and effort.

(I hated maths a school - you may have guessed).

his morning. I was solving a simultaneous equation with quadratics to prove a relationship between two apparently unconnected equations. I ended up with a quadratic to solve

How did you end up solving it?

Yeah maths is crap innit

Who needs it right.

Who needs it right

This is about the Quadratic formula. Not maths in general.

back to you.

2015. Came up in my accountancy exams.