Mega A Level Maths Thread MK II

256 * -0.75^n is not -196^n

what I'd suggest is on your second line, divide both sides by 256

Isn't it -192^n? i typed -192^n.
When dividing by 256 and simplifying and stuff I get n=13.047 this probably sounds stupid but why is the final answer 14?
Also, what was wrong with my method?

Ah right, sorry, but even still, that's not right, think about laws of indices. the exponential 'n' is only raised to -0.75, so if you did multiply them together, you'd still get 256*-0.75^n

Yep, that answer sounds about right. It's 14, because the question asks you for the smallest value of n, to which it exceeds 1000. technically, the smallest answer would be your 13.04... but you tend to round it to the nearest integer. It can't be 13 as that won't exceed 1000, as 13.04.. does, so it has to be 14.

Like I explained above, you just need to be careful when multiplying a number with a power that's raised to a number.

a * b = c

a * b^n =/= c (unless n=1)

Look at it practically, imagine n = 3, a = 5 and b = 2

5 * 2 = 6
5 * 2^3 = 40

what you did was:

5 * 2^3 = 10^3, which as you can see isn't right. Remember if a power is raised to a specific number, then it's only raised to that number

Thank you so much, this makes sense now

How do you work out percentage change for integration ???

LOGS QUESTION:::

Solve 4^(x) − 3(2^(x + 1)) = 0

QUESTION 5B SOLOMAN C CORE 2

http://www.tomred.org/uploads/7/7/8/3/778329/c2_qp_solomon_c.pdf

My workings:

log4^x = log6^x+1

Have I gone wrong?

I belive it is this $\dfrac{B-A}{A} \times 100$ and then put it as a percent, where B is the new value and A is the old value, this what I use for the inflation rate so it should work the same

I retook Unit 2 Economics last Friday as I wasn't happy with my Jan result (even though I got an A overall as AS), plus I wanted as much AS UMS as possible to guarantee at least an A overall for Economics.

Anyway, there was one question that gave 6 whole marks (80 raw marks total for the paper) just to calculate a new price index! I was like

Ah nice, think you did well ? Generally the OCR paper was a pile of piss so I can only expect high grade boundaries again, the essay question was a bit different from normal though, and those who neglected imports/exports failed it immediately. It was ''Discuss whether a high exchange rate will always reduce inflation'' Managed to make about 10 evaluation points haha. Lost 2 marks for calculations though, said average income per month was $45 because I can't type billions and millions into my calculator because I'm stupid

I decided not to retake unit 1, got 84 and I think I really smashed this one so hopefully 90 overall.

One question seriously for 6 marks with a calculation that takes like 20seconds? You must've being chuffed .

I think one of the recent edexcel papers has had a mistake ....anyone can do this mechanics sum please!

A ball is suspended from the roof of a moving car by a string, which is 7° to the vertical. Find the acceleration of the car.
Thy gave nothing about the mass etc.

How to do this?

Posted from TSR Mobile

Is that the whole question? What paper is this from?

That was the whole question.
Is this possible or not. Just say...don't try to do it..
Then I'll say from what paper.

Posted from TSR Mobile

If that's all the information, I don't think it's possible. I mean, only an angle was given...

However, I kind of doubt that was all the information given, so I'd like to see the paper for myself!

K thanks. So a student like you can't even do it.
I looked over every inch for any more data but there wasn't any.


Posted from TSR Mobile

So what's the paper!

K thanks. So a student like you can't even do it.
I looked over every inch for any more data but there wasn't any.


Posted from TSR Mobile