Christian Lawson-Perfect

Christian Lawson-Perfect on A randomised line in a GeoGebra worksheet - construct the definition of the line manually 8 years, 6 months ago

Gave some feedback: Should not be used

Christian Lawson-Perfect on Arithmetic sequences in an ice cream shop 8 years, 6 months ago

Gave some feedback: Has some problems

Christian Lawson-Perfect commented on Arithmetic sequences in an ice cream shop 8 years, 6 months ago

In part c, I'd ask the student to give an expression for $a_n$ in terms of $n$ before getting them to compute a value. (Or, ask for $a_n$ at a particular small $n$ to check they've got the correspondence right, then ask for an expression, then calculate $a_n$ for a given big $n$)

Part d smells a lot like a fake context. Suppose you're Jenny, and you want to know how many other customers have had the strawberry ice cream before you. What information do you have? You wouldn't be told "the 1st, 6th, 11th, ... customers receive strawberry". You'd either be told "there are five flavours, and the shops cycles through them", or you'd notice that people 5 and 10 places in front of you in the queue also got strawberry. You also need to give a reason for Jenny to know which number customer she is. 

Maybe turn it around slightly: Jenny counts $x$ people buy ice creams before her, and the people $y$ and $y+a$ places in front of her got strawberry. How many people were given strawberry before Jenny?

Christian Lawson-Perfect commented on Arithmetic sequences in an ice cream shop 8 years, 6 months ago

Before I even look at this question: never say "basic"!!!

Christian Lawson-Perfect on Solve quadratic inequalities 8 years, 6 months ago

Gave some feedback: Ready to use

Christian Lawson-Perfect on Solve quadratic inequalities 8 years, 6 months ago

Saved a checkpoint:

I've fixed a couple of typos, but otherwise this is OK!

Christian Lawson-Perfect on Finding the full factorisation of a polynomial, using the Factor Theorem and long division 8 years, 6 months ago

Gave some feedback: Ready to use

Christian Lawson-Perfect on Finding the full factorisation of a polynomial, using the Factor Theorem and long division 8 years, 6 months ago

Saved a checkpoint:

I've added a script to make sure the answer is fully factorised.