Year 13 Maths Help Thread

Find y' and y'' and then just plug it into the equation and compare coefficients.

Part iii

For $y=(-1)^x$, do we write $f:\mathbb{R} \rightarrow \mathbb{Z}$ for the domain and codomain?

That's not a function if you choose that domain.

Would $f:\mathbb{Z} \rightarrow \mathbb{Z}$ make it a function?

lol np, I am glad (and surprised) I could help out I am guessing you are studying some M units, how many have you done so far?

Part way through M2 and I will be doing M3 as well, was originally going to do M3,4 and 5 but I'd rather focus on M3 and the rest of the further modules (FP1,2,3 M2,3 D1 and S2 I'll be doing)


What about you?

Hey, I want to see what someone else gets because im confused as to why my answer is wrong.

By what percentage is the heaviest girl heavier than the lightest girl (to the nearest whole number)?
if the heaviest = 143 lb and the lightest = 111lb.
What answer did you get?


I got 22 %

I did M1 in my first year and got 70 ums (impressive, ik), I decided to stick with mechanics and try M2 and did a bit better, but still pretty bad lol (80 ums). I was actually really disappointing with M2 because it was like my lowest A2 exam by quite a way in any subject. I also thought that I had only got one problem wrong from the model answers, so I think I possibly lost marks for working out??
That would be my biggest tip for mechanics, make sure your diagrams are very clear - as like most of the M2 marks are for the set up of the initial equations and the diagrams are part of that.
I never really got on particularly well with mechanics in all honesty. It took me a while to learn and it doesn't go that well with my other subjects and is unlikely to be useful to me in the future! But I'm glad I did the little bit I did

can someone help me with this complex numbers problem? it's under the subtopic of polar notation.
The main bit I don't really understand is that AB^2 = 39. For me, as A & B both contain i, AB^2 should have i^3 in it so can't = 36. I don't understand it lol
@Zacken maybe?

can someone help me with this complex numbers problem? it's under the subtopic of polar notation.
The main bit I don't really understand is that AB^2 = 39. For me, as A & B both contain i, AB^2 should have i^3 in it so can't = 36. I don't understand it lol
@Zacken maybe?

I think the question is just using excessively bad notation and means that the distance between A and B^2 is 39. Not the complex numbers A multiplied by B^2 is 39.

it means the modulus is sqrt39

yes that does make sense, although I feel like it should have brackets or one of the vector arrows!!!

it annoys me too

thanks for your help @Zacken as well. next step is to remember the cosine rule, which I feel I genuinely haven't used in 2 years lol