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So who wants to help with a maths problem Im very confused about? Its apart of the easy section but I kinda dont get it.

This is the problem:

a=0 b=-1 c=-3

√3a+2b²-c³

I do the square root last because on the equation it is over all of the numbers.
So the answer on the calculator without square rooting it is 25. but when I work it out myself I keep getting 29. This is how I worked it out my way

(3x0) + (2x-1²) - (-3³)
0 + 2 - -27
2 - -27
29 (but for some reason the calculator thinks its 25)

Here is where I get confused, because when you subtract a negative number it will turn into an addition, I even looked it up and used the calculator to work out 2-(-27) and it equaled 29. SO HOW IS IT WHEN I PUT THE WHOLE EQUATION (MINUS THE SQUARE ROOT) I GET 25. I dont get it man, maths is confusing or maybe im just overthinking it. SOmeone tell me im just making a stupid mistake or something

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Mark667788 · 46-50, M

Try putting the -1 and -3 in parentheses with the exponent outside in the calculator. The answer is 29.

Faust76 · 46-50, M

Probably the calculator has different button for negative numbers and substraction, but you're using the substraction button twice? Or not that simple? I think I used to make that mistake sometimes though ^^

ShepherdBard · 31-35, M

@Faust76 I think it may be something along these lines. If you do minus button when you are squaring negative one, it will return negative one.

Faust76 · 46-50, M

@ShepherdBard I'm assuming parentheses, if supported by the calculator, are in the right places. I found my old school calculator and tried it out, and if I enter "2 - - 27" there's no visual indication anything goes wrong but it does indeed return 25, which is weird. I get it might take the first - to negate the 2, but why would it then sum the second number? (-2)-(-27) how does that figure?

Most calculators have +/- key for changing the sign though, or (-) on graphing calculators. I found few examples of calculators without separate sign-flip button, but for the most part they have one, which can be problematic because in human mathematics we rarely (I think) make a distinction between the signedness of the number and the mathematical operation.

Of course, if the goal is just to, I don't know, verify the result or whatever then simply breaking the problem into pieces and using calculator to verify each one separately. This should also let one see where the error happens (Well, assuming one CAN tell whether the calculator or they themselves made the error). Learning HOW to do it with the calculator kinda depends on the calculator though. My functional calculator lets me just enter the inside of the root as-is with no parentheses (Because the terms are multiplications) as long as I use +/- button to change the sign of the base, and get 29. Same thing with writing the exponentiation open.

My graphing calculator looks to be broken though, bugs ate it.

ShepherdBard · 31-35, M

@Faust76 interesting there can be so many variables between the different calculator

ClanNaFiacaillApWythe · 51-55, M

Trivial it is as u just need to know and implement the order of operations rubric correctly. b squared is one. c cubed is - 27. Ignore the a. Then we have 2 + 27 = 29. There it is.

SeductiveCactus · 26-30, F

@ClanNaFiacaillApWythe thank you very much! The calculator was confusing me way too much 😓

ClanNaFiacaillApWythe · 51-55, M

@SeductiveCactus Calculators are little computers. They have speed but no understanding. They do exactly what they are programmed to do, no more and no less. These are simple binary operations that they do that lead up to the results of base 10 arithmetic. All interpretation and ordering has to be done by the operator.

ClanNaFiacaillApWythe · 51-55, M

Also don't get so hung-up over calculators and computers. They have no judgement and awareness and just perform operations quickly.

TacoCat · 26-30, M

Why does math have letters

SeductiveCactus · 26-30, F

@TacoCat right?! Like Pls just stop

TacoCat · 26-30, M

@SeductiveCactus next thing they'll put is Ancient hieroglyphics

SW-User

Sorry, I don’t have time for wizardry.

SeductiveCactus · 26-30, F

@SW-User traitor

UserNameSW · 46-50, M

2 minus -27 is -25.

SeductiveCactus · 26-30, F

@UserNameSW no, when you're subtracting a minus number that just turns into a plus. If it was 2-27 then yeah, but it's not. It's positive 2 - negative 2.

REMsleep · 41-45, F

Well exponents should be done prior to all other multiplication, adding or subtracting so -3*-3*-3=-27+2=-25
Maybe that's it and once you square it the negative doesn't matter.

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