Relations and Functions Worksheet Form

Years ago I worked at document management company.  There is cool software that can automate aspects of hand-written forms.  We had an airport as a customer - they scanned plenty and (as I said before) this was several years ago...On your airport customs forms, the "boxes" that you 'need' to write on - are basically invisible to the scanner - but are used because then us humans will tend to write neater and clearer which make sit easier to recognize with a computer.  Any characters with less than X% accuracy based on a recognition engine are flagged and shown as an image zoomed into the particular character so a human operator can then say "that is an "A".   This way, you can rapidly go through most forms and output it to say - an SQL database, complete with link to original image of the form you filled in.If you see "black boxes" at three corners of the document - it is likely set up for scanning (they help to identify and orient the page digitally).  If there is a unique barcode on the document somewhere I would theorize there is an even higher likelihood of it being scanned - the document is of enough value to be printed individually which costs more, which means it is likely going to be used on the capture side.   (I've noticed in the past in Bahamas and some other Caribbean islands they use these sorts of capture mechanisms, but they have far fewer people entering than the US does everyday)The real answer is: it depends.  Depending on each country and its policies and procedures.  Generally I would be surprised if they scanned and held onto the paper.   In the US, they proably file those for a set period of time then destroy them, perhaps mining them for some data about travellers. In the end,  I suspect the "paper-to-data capture" likelihood of customs forms ranges somewhere on a spectrum like this:Third world Customs Guy has paper to show he did his job, paper gets thrown out at end of shift. ------>  We keep all the papers! everything is scanned as you pass by customs and unique barcodes identify which flight/gate/area the form was handed out at, so we co-ordinate with cameras in the airport and have captured your image.  We also know exactly how much vodka you brought into the country. :)

Think of a function as a machine. You put a number in, and you get a different number out. Some machines will take any number you give them; others don’t work on some numbers. Some machines will (eventually) spit out just about any number you can imagine; other machines are known to only produce some numbers but not others.“Domain” means the numbers you feed to the function. “Range” means the numbers it gives back to you.For example, think of y=3x. You can plug any number you want in for x, so the domain of this function is “all real numbers” (or everything from negative infinity to positive infinity, if you like). And you can probably figure out that any real number could come out of it too. (You want a certain real number to come out? Plug in one-third of that number for x, and there you go!) So the range of this function is also “all real numbers”.But suppose your function is y=x^2 (the simplest possible quadratic). Your domain is still all real numbers. But any real number, squared, will result in a positive number… so the range would be “all non-negative real numbers” (or, if you prefer, “all positive real numbers and also zero”).In short, if you think of domain as “all possible inputs” and range as “all possible outputs”, you’ll have the right idea.

The parameter methodIf you have each function given explicitly, say f(x) = x+3 and g(x)=x^2 and you want to find the domain and range of g(f(x)) then the easiest thing to do is form a function in one variable by passing the parameter through. So g(f(x))=g(x+3)=(x+3)^2. Finding the domain and range of this is simple, it's just a normal function. This method applies for higher orders of composition too. However, if you don't have the functions explicitly (we’re not always that lucky) or want to think about it in terms of sets read below.The set methodLet's say our composite function is g(f(x)). The easiest way to determine domain and range is to split the functions up.Start by taking f(x). Determine the range of that function. Take g(x) and determine it's domain. Do this as if they were individual functions - this should be fairly easy.Now take the intersection of those two sets, call it X. This is the set that links the two functions, it is mapable from the domain of g(f(x)) by carrying out f, and its mapable to the range of g(f(x)) by carrying out g.The domain of g(f(x)) is the preimage of X in f, or if you prefer f^-1(X)=Y. The range of g(f(x)) is g(X)=Z.This forms the sequence of equivalences g(f(Y))=g(X)=Z. So Y is the domain and Z is the range. This should be clear by f: Y → X and g: X → Z.This process can be extended to more highly composite functions such as f(g(h(x))) but requires a bit more moving backwards and forwards. I would start by determining the domain and range of g(h(x)) as above. Then carry out the process of intersecting the domain of f with the range of g(h(x)), call it X. You should then be fairly easily be able to get the total range by calculating f(X)=W. You'll then need to work back to determine the final domain of g(h(x)) that is allowable. To do this you carry out the preimage of g on X, I.e. g^-1(X) = Y. Then carry out the preimage of h on Y, I.e h^-1(Y) = Z. This gives the final domain.Written more nicely we will have found h: Z → Y, g: Y → X and f: X → W where Z is the domain and W is the range of f(g(h(x))).I hope this explanation helps. The set methodology requires a bit of thought but after some examples it becomes easier. If anyone has any examples they need help with feel free to comment or request me to answer another question and I'll get round to it.

Departments of education and school districts always have to make decisions about what to include in their curriculum.  There are a lot of life skills that people need that aren't taught in school.  The question is should those skills be taught in schools?I teach high school, so I'll talk about that.  The typical high school curriculum is supposed to give students a broad-based education that prepares them to be citizens in a democracy and to be able to think critically.  For a democracy to work, we need educated, discerning citizens with the ability to make good decisions based on evidence and objective thought.  In theory, people who are well informed about history, culture, science, mathematics, etc., and are capable of critical, unbiased thinking, will have the tools to participate in a democracy and make good decisions for themselves and for society at large.  In addition to that, they should be learning how to be learners, how to do effective, basic research, and collaborate with other people.  If that happens, figuring out how to do procedural tasks in real life should not provide much of a challenge.  We can't possibly teach every necessary life skill people need, but we can help students become better at knowing how to acquire the skills they need.  Should we teach them how to change a tire when they can easily consult a book or search the internet to find step by step instructions for that?  Should we teach them how to balance a check book or teach them how to think mathematically and make sense of problems so that the simple task of balancing a check book (which requires simple arithmetic and the ability to enter numbers and words in columns and rows in obvious ways) is easy for them to figure out.  If we teach them to be good at critical thinking and have some problem solving skills they will be able to apply those overarching skills to all sorts of every day tasks that shouldn't be difficult for someone with decent cognitive ability  to figure out.  It's analogous to asking why a culinary school didn't teach its students the steps and ingredients to a specific recipe.  The school taught them about more general food preparation and food science skills so that they can figure out how to make a lot of specific recipes without much trouble.  They're also able to create their own recipes.So, do we want citizens with very specific skill sets that they need to get through day to day life or do we want citizens with critical thinking, problem solving, and other overarching cognitive skills that will allow them to easily acquire ANY simple, procedural skill they may come to need at any point in their lives?

In California, it is “actionable” to be required to do that on your _own_ time.In short, if a company requires work that’s unpaid and you’re not on salary (are an hourly employee, but not being paid that hourly rate for said work), then you could sue them and/or bring it up to your state’s labor board as a potential violation.Meaning, any company that requires this sort of work to be done without payment as such would do well to review that policy with legal counsel.Note: We (SwiftCloud ) have legal staffing firm clients and attorney clients, but are not an attorney. Laws for your state or jurisdiction will vary.

-R2A-Since you have been working out problems at such level, I assume you are quite familiar that the denominator can’t be zero.[math]\Rightarrow \ [|x-1|] + [|x-7|] - 6 \neq \ 0 [/math]Clearly, we have greatest integer function involved  here which plays a greater role in extracting out the integral part for real numbers. So, the region of suspicion for any changes are all the intervals between consecutive natural numbers from 1 to 7 as well as those natural numbers themselves.So, it’s better if we do a quick work out on how each term behaves in each interval and at each natural number.From above table, we can easily write the domain as R - ((0,1) U {1,2,3,4,5,6,7})A. This option can be ruled out as x=7 also results in zero.B. This option can be ruled out too. Although it covers all the natural numbers but not all the intervals results in zero.C. It’s represented in a confusing way. Let’s rewrite it in a simple manner. R -( (0,1] U {2,3,4,5,6,7})  ——  Yes!! This is our solution.D. Another confusing representation, let’s simplify it.  R -  {2,3,4,5,6} .  Whoa!! It’s even worse compared to option A.It might appear a time-taking task but it isn’t!! I barely spent 2 minutes solving it on my sheet.I hope it helps!

For this type of function, the domain is all rEval numbers. A function with a fraction with a variable in the denominator. To find the domain of this type of function, set the bottom equal to zero and exclude the x value you find when you solve the equation. A function with a variable inside a radical sign.

Another way to identify the domain and range of functions is by using graphs. Because the domain refers to the set of possible input values, the domain of a graph consists of all the input values shown on the x-axis. The range is the set of possible output values, which are shown on the y-axis.

In the set of ordered pairs {(-2, 0), (0, 6), (2, 12), (4, 18)}, the domain is the set of the first number in every pair (those are the x-coordinates): {-2, 0, 2, 4×. The range is the set of the second number of all the pairs (those are the y-coordinates): {0, 6, 12, 18×. This table describes y as a function of x.

The range of a function is the complete set of all possible resulting values of the dependent variable (y, usually), after we have substituted the domain. In plain English, the definition means: The range is the resulting y-values we get after substituting all the possible x-values.

In the set of ordered pairs {(-2, 0), (0, 6), (2, 12), (4, 18)}, the domain is the set of the first number in every pair (those are the x-coordinates): {-2, 0, 2, 4×. The range is the set of the second number of all the pairs (those are the y-coordinates): {0, 6, 12, 18×. This table describes y as a function of x.