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Maths Equation - Help
perksy - 4/3/12 at 09:55 PM

Know there's some bright lads on here


Sorry to be thick, but what does the * symbol mean in an equation ?


ie If a * b means 3a divided by b Find the values of 2 * 5 ?




Thanks in advance for any help

Can strip & rebuild a Weber Carb or an engine but maths ain't my thing

daviep - 4/3/12 at 10:02 PM

multiplied by

Tiger Super Six - 4/3/12 at 10:03 PM

Usually a * means 'times by' like normally means 'divide by'.

dray13dad - 4/3/12 at 10:05 PM

Had to ask my daughter as she's the Maths spark round here, but she has said, that usually the * in an equation means multiplication, so a*b=a x b. However if you're stating that in this case a * b means 3a divided by b, then 2 * 5= (2 x 3)/5=6/5=1.2.

Also if you have any Weber bits going spare, then I'd be more than interested. Hope this is of some help, if not I'll be asking her again!

perksy - 4/3/12 at 10:20 PM

Ahh So * means x (or multiplied by) Thanks



I wrote the question wrong sorry


It should have read a * b means 3a + b Find the value of 2 * 5 ?





Sorry i haven't got any Weber bits going spare, Well i've got a pair of 40's here but there not mine

loggyboy - 4/3/12 at 10:44 PM

where there is no symbol, it also means multiply.
ie 3a = 3xa

matt_gsxr - 4/3/12 at 10:48 PM

sometimes people use a "." too

morcus - 4/3/12 at 10:50 PM

Surely it can't mean multiply in this situation? If it does then the first half of the question is meaningless as it would translate as if ab=3a+b work out 2x5=?.

THIS looks like your using it to denote convolution from the options given. I can't remember enough right now to undersand fully what the question means if that is the case, I'm guessing 2 and 5 are the boundries and your working out the area under the graph 3a+b between 2 and 5 which I think is -21/6 but as I say, I'm probably well off the mark.

Chippy - 4/3/12 at 11:06 PM

Well long time since I was at school, but a*b = 3a+b works out at 2 x 6 = 12, so 3 x a = 6 + 6 = 12. Have no idea what the next bit comes too though, Cheers Ray

Peteff - 4/3/12 at 11:38 PM

I got the last bit, 2*5=10

Daddylonglegs - 5/3/12 at 07:39 AM

quote:
Originally posted by Peteff
I got the last bit, 2*5=10


Oooh, Oooh, Oooh! Me too!

scudderfish - 5/3/12 at 01:00 PM

quote:
Originally posted by perksy
Ahh So * means x (or multiplied by) Thanks



I wrote the question wrong sorry


It should have read a * b means 3a + b Find the value of 2 * 5 ?





Sorry i haven't got any Weber bits going spare, Well i've got a pair of 40's here but there not mine


In this context, it looks like '*' is being defined as a new function, not multiplication (would have been easier if whoever set the question had used a non-mathematical symbol like # or @)

So 'a*b' means '3 x a + b'

'2 * 5' means ' 3 x 2 + 5' = 11

perksy - 5/3/12 at 07:29 PM

Ahhh ok then starting to make some sense now
Don't think it was that well written to be honest and it was from a GCSE Maths assignment paper


Thanks very much for the help on this one lads, Much appreciated