Elliott Fletcher commented 7 years, 5 months ago

Yeah i think there is an always/sometimes/never question already for this.

Chris Graham 7 years, 5 months ago

Gave some feedback: Ready to use

Chris Graham commented 7 years, 5 months ago

This is OK. I'm not sure if we wrote an always/sometimes/never question, but if we didn't then it would be an excellent addition.

Stanislav Duris 7 years, 5 months ago

Saved a checkpoint:

If this question isn't ready and someone needs to adjust this question - make sure that the interval in part c) always includes one square number only! The x variable makes sure the numbers increase in ascending order in the question, so don't confuse x1, x2, etc. with x[0], x[1],.. because these may not be the same and x[0], x[1],.. are the ones used in the question.

Restore this checkpoint

Stanislav Duris 7 years, 5 months ago

Gave some feedback: Needs to be tested

Christian Lawson-Perfect 7 years, 5 months ago

Gave some feedback: Has some problems

Christian Lawson-Perfect 7 years, 5 months ago

Saved a checkpoint:

I don't think you need the $x_i$ notation. This question should test that the student knows what a superscript 2 or 3 means. This question could just be, "Find $5^2$"; "Find $3^3$"; "Find the first square number between $124$ and $165$".

Restore this checkpoint

Elliott Fletcher commented 7 years, 5 months ago

Main Parts

a) i would write (x_n)^2 instead of x^2.

b) i would write (x_n)^3 instead of x^3. Also, its up to you but you could maybe include (x_5)^3 as an extra question here.

c) i think there should be a full stop after the inequality here.

Advice

a) i think there should be full stops at the end of each of the calculations, like after the 9 in the calculation for 3^2.

b) again i think there should be full stops at the end of each of the calculations.

c) i would say "Here is a table of square numbers for integers from 1-15"

I would also include an extra sentence before you calculate the square root of y^2. You could say "To calculate y we must calculate the square root of y^2," and then have a full stop at the end of the equation here as well.

Otherwise, this looks good!

Stanislav Duris 7 years, 5 months ago

Gave some feedback: Needs to be tested

Christian Lawson-Perfect 7 years, 5 months ago

Gave some feedback: Has some problems

Christian Lawson-Perfect commented 7 years, 5 months ago

I don't think part a is a well-conceived question. First of all, I don't like telling students not to use calculators. You can sometimes hint that a calculator won't be useful, but don't give them the idea that using calculator is ever bad.

When you're told $x$ and $x^3$ but not $x^2$ - why would you ever calculate $(x^3)^{2/3}$ instead of just squaring $x$?

Similarly, when you're given $x^3$ and $x^3$ but not $x$, I don't think anyone would take the cube root instead of the square root. So why show both?

Some ideas for different questions on the same topic:

• Calculate $x^2$ for $x$ from 1 to 10.
• Calculate $x^3$ for $x$ from 1 to 10.
• Find a number such that $x^2 \gt 100$ and $x^2 \lt 120$.
• An "always/sometimes/never" question for some statements. The student has to say if each of the statements is always true, sometimes true, or never true.
  • $x^3$ is greater than $x^2$. (sometimes)
  • If $x$ is negative, $x^2$ is negative (never)
  • If $x$ is negative, $x^3$ is negative (always)
  • $x^2 = x$ (sometimes)
  • $(x+1)^2 \gt x$ (sometimes)
  • $(x+1)^3 \gt x$ (always)
  • When $x$ is a whole number, $x^2$ divides $x^3$ (always)
  • $x^3$ has the opposite sign to $x$ (never)

Part b is good - it could be a separate question, called "calculate powers of ten"

Stanislav Duris 7 years, 6 months ago

Gave some feedback: Needs to be tested