Tag Archives: proof

302. Log Proof Puzzle

If you can guess where today’s blog image came from you obviously consume too much damn fine cherry pie and fresh coffee!

log lady

Image credit: Pinterest

You may have guessed that the topic of this post is logs. If you are introducing the rules for adding and subtracting logs or revising them, I have just the resource for you. It’s a basic proof of both rules with a twist. The instructions are in the wrong order and you must rearrange them into the right order.


Are you sure?

For those of you who have a student or two who rush everything and don’t read the instructions there is a sting in the tail. One of the lines of proof is a tiny bit wrong. The methodical student will find it, the one who races through may end up changing more than one line – hence breaking the rules.

Have fun!

Proving log rules for addition and subtraction

Answer: It’s the ‘Log Lady’ from the cult classic ‘Twin Peaks’!

244. Resource of the Week

I recently came across this splendid resource for introducing Sine and Cosine rule to students.

Proving the Sine and Cosine rule

The proofs for these rules are relatively simple, but getting a class of teenagers to engage with it is a different matter! These worksheets give you the proofs, step by step, but all jumbled up. Students must rearrange the stages in order to create a proof. It worked brilliantly!

Thank you @mrslack_maths