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Published this.

#### Christian Lawson-Perfect2 years, 6 months ago

Gave some feedback: Ready to use

#### Christian Lawson-Perfect2 years, 6 months ago

Saved a checkpoint:

Good stuff!

#### Elliott Fletcher2 years, 6 months ago

I did try to make it so that s and t were always integers but i think there are so many numbers involved in the calculation that it would be very difficult to do. Instead i have restricted the values that the variables can take to make the fractions in the answers slightly nicer.

I see what you mean about the error message, i'm not sure how to fix this but i have said that you can leave your answer as a fraction in the question.

I have also split the question up into parts to make it more accessible to students with less algebraic skill.

#### Elliott Fletcher2 years, 6 months ago

Gave some feedback: Needs to be tested

#### Bradley Bush2 years, 6 months ago

Gave some feedback: Has some problems

#### Bradley Bush2 years, 6 months ago

Amazing question, most of my feedback revolves around the idea that I think it might be too hard for the student so I only have a few comments on this one:

• I didn't find an example of when s and t weren't both fractions, I think this adds to the complexity and the challenge of the question but is this what we want to be testing? Could this be imporved through making the variables 'nicer' so the answers are whole numbers more often than not?
• If you are leaving the answers as their more complex fraction form then you need to have a go at changing the error message that comes up. The answer gap still accepts a fractional answer if you type the fraction in full, however, if you're slow like me and you type "x/" and then pause for a second, you'll get an error message "your answer is invalid. You must enter an integer or a decimal. This is weird because when you then finish the expresion, the error message goes away. I am just thinking that this might be misdirective to see for anyone typing in their answer slowly. If you can't fix the error message, and you are keeping the fractional answers then it might be worth specifying that answers can be left as fractions in the question.
• On that note, I might write "reduce your answer to simplist [fractional] form" instead of "reduce your answer to it's lowest terms"; or something along those lines.
• I am actually thinking that the question still might be too hard for some students, making it inaccessible to the students who have less algebraic skill; even with the changes I suggested above. Maybe a solution of this is to create a copy of the question (labelling it 'easy version') and have the same question, just break it down into parts by asking students to give an expression for p(factor 1) then p(factor 2) then with the third part asking them to use simultaneous equations to find t and s.
• Your parts and advice seem free of typos and formatting errors (I'm very jealous).

Feel free to ask if you don't understand any of what I've been getting at. High quality question.

#### Elliott Fletcher2 years, 6 months ago

Gave some feedback: Needs to be tested

#### Elliott Fletcher2 years, 7 months ago

Created this.
Finding unknown coefficients of a polynomial, using the remainder theorem Ready to use Elliott Fletcher 20/11/2019 14:39
George's copy of Finding unknown coefficients of a polynomial, using the remainder theorem draft George Loughlin 06/07/2017 15:09
Encontrar coeficientes desconocidos de un polinomio, usando el teorema del resto Ready to use Luis Hernandez 15/01/2019 03:38
Simon's copy of Finding unknown coefficients of a polynomial, using the remainder theorem draft Simon Thomas 28/02/2019 12:15
Finding unknown coefficients of a polynomial, using the remainder theorem draft Johnny Yi 30/04/2019 03:19
Christian's copy of Finding unknown coefficients of a polynomial, using the remainder theorem draft Christian Lawson-Perfect 20/05/2019 13:55
Finding unknown coefficients of a polynomial, using the remainder theorem draft Xiaodan Leng 10/07/2019 21:44

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