difficut maths queston

FF and proud

i saw a maths question there in the paper that had a prize and it was terible hard. i was thinkingg maybe ye maths nerds culd help me out.

square roots of four minus 2 mutaplyid by 5

Mellor

Assuming it was written like that in the paper, and not with any other symbols such as brackets.
We can write it as;

√4 - 2 x 5

According to the order of operatinos, indices and multiplication take preference over addition so it then becomes

2 - 10

Which can be easily solved as -8

dermiek

Mellor wrote: »

Assuming it was written like that in the paper, and not with any other symbols such as brackets.
We can write it as;

√4 - 2 x 5

According to the order of operatinos, indices and multiplication take preference over addition so it then becomes

2 - 10

Which can be easily solved as -8

It could also be (√4 - 2) x 5 which is 0 x 5 or 0

Mellor

No it couldn't. Don't be ridiculous
You just added brackets which completely change the equation. You can't jsut add things like that in.

I cleary stated
Assuming it was written like that in the paper, and not with any other symbols such as brackets"
If thats the way it was written in the paper, then adding brackets is wrong.

I imagine the puzzle was to spot that 2x5 takes place over 2 - 2, thus avoiding the multiplication by zero.

dermiek

Who rattled your cage? I'm just showing another way of solving it which is possible. I assumed that the maker of the puzzle wanted people to assume what you assumed, when assuming what you assumed was the wrong assumation.

I assume.

Turtwig

dermiek wrote: »

Who rattled your cage? I'm just showing another way of solving it which is possible. I assumed that the maker of the puzzle wanted people to assume what you assumed, when assuming what you assumed was the wrong assumation.

I assume.

LOL wut?

In maths there are conventions you follows. '-' means this, '+' means this. When given an expression you move from left to right but various operations have different orders of precedence.
Putting in arbitrary brackets for no reason is not one of them.

Pherekydes

Mellor wrote: »

Assuming it was written like that in the paper, and not with any other symbols such as brackets.
We can write it as;

√4 - 2 x 5

According to the order of operatinos, indices and multiplication take preference over addition so it then becomes

2 - 10

Which can be easily solved as -8

Or -12.

sponsoredwalk

Zoozlefrazzle

Davidius

sponsoredwalk wrote: »

Zoozlefrazzle

I can't believe how many people got that wrong. The answer is very clearly closer to 15 than either of those (in some base I'm sure).

TommyTippee

FF and proud wrote: »

i saw a maths question there in the paper that had a prize and it was terible hard. i was thinkingg maybe ye maths nerds culd help me out.

square roots of four minus 2 mutaplyid by 5

It's english "nerds" you need. Learn how to write and come back to us.

This is your average Fianna Fail voter....illiterate.

Mellor

Pherekydes wrote: »

Or -12.

2 - 10 is -8 not -12

PseudoFamous

Mellor wrote: »

2 - 10 is -8 not -12

4 has two roots: 2 and -2. Thus, it could be either -8 or -12 in that context.

Mellor

PseudoFamous wrote: »

4 has two roots: 2 and -2. Thus, it could be either -8 or -12 in that context.

Yeah, thought of that just after I posted. Well spotted Pherekydes

Davidius

Well from a technical point of view √4 is 2, while the solutions to x^2 = 4 are 2 and -2. They did specify square roots though.

Michael Collins

Davidius wrote: »

Well from a technical point of view √4 is 2, while the solutions to x^2 = 4 are 2 and -2. They did specify square roots though.

Exactly. It depends on whether the question in the paper was stated using the term "square root" or written using the radical sign.

gerardduff

This is just FF creating confusion again. Practicing for the next time they get in to government.