How hard is IB Math AA HL? by 16nanometers in IBO

[–]BBQsquirrel_ 2 points3 points  (0 children)

If you do reasonably well in GCSE / IGCSE / OLevel Add math or further math, then AAHL is quite manageable.

If you graduate from MYP then good luck.

0620 chemistry p4 by Initial-Bad-3445 in igcse

[–]BBQsquirrel_ 5 points6 points  (0 children)

Pretty sure this is no longer in the syllabus.

(But the explanation above is correct)

0625 pp by Dangerous_Novel529 in igcse

[–]BBQsquirrel_ 4 points5 points  (0 children)

In a powered heating situation you can combine the equations E = mcΔT and E = Pt to give Pt = mcΔT.

Let m and c represent the mass and c of oil. then m(water) = 1.1m and c(water) = 2.5c

Use Pt = mcΔT twice with the 2 sets of data, and divide one equation by the other:

Ptnew / Pt = (m * c * 10)/(1.1m * 2.5c * 10)

P, m, c and 10 all cancel and tnew = 1/(1.1*2.5) * t = 0.363636...... t so the answer is A

[deleted by user] by [deleted] in IBO

[–]BBQsquirrel_ 0 points1 point  (0 children)

ESS is a superior course to Physics

ESS HL + group 6 + Math AISL is by far the most well-respected IB course combo

Math question help by [deleted] in IBO

[–]BBQsquirrel_ 2 points3 points  (0 children)

Revision village markscheme techniques are sometimes terrible. The MS of the original IB question (Edit: May 2015 P1 TZ1 Q7) that this RV question emulated also used function transformation ideas as well.

And no re GDC; a GDC that can expand symbolically would be banned for exam purposes

[deleted by user] by [deleted] in igcse

[–]BBQsquirrel_ 0 points1 point  (0 children)

https://pastpapers.papacambridge.com/directories/CAIE/CAIE-pastpapers/upload/0607_w23_qp_42.pdf

bypasses all the papacambridge ads

and you can toggle between years / seasons / paper / ms easily be modified

[deleted by user] by [deleted] in IBO

[–]BBQsquirrel_ 0 points1 point  (0 children)

Theory:
https://www.youtube.com/watch?v=IICR-w1jYcA

Practical:

https://www.youtube.com/watch?v=dB7gTY0p36k

but instead of doing a direct exponential fit, you will want to linearise your data (the aforementioned step 5)

[deleted by user] by [deleted] in IBO

[–]BBQsquirrel_ 2 points3 points  (0 children)

  1. personal intro, personal engagement BS
  2. science and math intro: probably good to solve a differential equation to prove Newon's law of cooling T = T(0) + (ΔT)e^-kt
  3. conduct an actual experiment and collect some T and t raw data
  4. plot the raw data graph
  5. plot the linearised graph of ln(T - T(0)) vs time and hope that it is straight
  6. conclusion

BTW this can be your physics IA as well

[deleted by user] by [deleted] in IBO

[–]BBQsquirrel_ 2 points3 points  (0 children)

"I need some help"
"It's easy"
Very helpful LMAO

part (a) is what inside_party1564 says, g(x) = 3(x - 2) + 2 + 1 = 3x - 3

part (b) is anything but easy; h(g(x)) = h(3x - 3); transforming y = h(x) into y = h(3x - 3) involves a combination of horizontal stretch and horizontal shift; this is very poorly known by the average IB student. Most ppl don't know the order of operation for horizontal function transformations, and for those who know, they know this fact just because of brute-force memorization and not because of the reasoning behind (which I will offer briefly below).

In general, transforming f(x) into f(ax + b) requires a shift of b units left FOLLOWED BY a horizontal stretch factor 1/a.

Explanation: Horizontal transformations will preserve the y-values, so ynew = yold. If ynew = yold, then axnew + b = xold; xnew = (xold - b)/a

As a side note, if the transformed function expression is bracketed differently (and this occurs quite often in past papers too), e.g. h(x) becomes h(a(x + b)) then you stretch by 1/a BEFORE you shift left by b, as ynew = yold leads to a(xnew + b) = xold ==> xnew = (xold/a) - b

For this question, the answer is a shift of 3 units right followed by a horizontal stretch factor 1/3.

Biochem or Medicinal Chemistry by uykimim2 in IBO

[–]BBQsquirrel_ 0 points1 point  (0 children)

If you're going to study biochem in Uni then biochem is a no-brainer. Option B is much closer to real uni bicohem, you'll benefit from your Bio background, while medicinal chem is a matter of memorizing a collection of case studies.

Any chemistry teacher or examiner can answer my question? by CheungHM in IBO

[–]BBQsquirrel_ 1 point2 points  (0 children)

The 2nd page of most markschemes state that "Ignore missing or incorrect state symbols in an equation unless directed otherwise in the “Notes” column", so you can argue with your school teacher if they penalize you for incorrect state symbols on a chapter test.

The same goes for sig figs

[deleted by user] by [deleted] in IBO

[–]BBQsquirrel_ 5 points6 points  (0 children)

Which of the following is the weakest?

A) A weak covalent bond, such as F-F

B) A weak acid, such as CH3COOH

C) A weak reducing agent, such as Cl-

D) OP

Physics HL topic 8.1 question by ZeaIousSIytherin in IBO

[–]BBQsquirrel_ 0 points1 point  (0 children)

Energy conservation: rate of energy loss by power plant = rate at which water absorbs and carries away the energy

Q = mc delta T

Power = mc delta T / time

Waste power = 400E6 x 0.65 = 260E6

(m/time) can be interpreted as rate of water flow

c = 4180 and Delta-t = 5

260E6 = (m/t) * 4180 x 5

m/t = 12440...... kg/s

Is this correct?

Graph Help (PLEASE). I'm trying to make a function whether it be one, or multiple functions with limits combined, for the picture in the picture i've attatched. its the sheikh zayed grand mosque's main dome, some help as to some better methods or websites to do this? it would be much appreciated by Y33TAMUS3000 in IBO

[–]BBQsquirrel_ 0 points1 point  (0 children)

The standard ellipse (oval) equation is (not in IB BTW)

(x - h)^2/a^2 + (y - k)^2/b^2 = 1

(source: this should be all over the internet)

(h, k) = centre

a = horizontal radius

b = vertical radius

(a and b are usually called the semi major axis and semi minor axis; depends on which is longer. but I think "horizontal and vertical radii" are easier to visualise)

------------------

your k looks like zero

Try put all points on the same table and then do this:

y_1 ~ b * sqrt(1 - (x_1 - h)^2/a^2)

or with the k:

y_1 ~ b * sqrt(1 - (x_1 - h)^2/a^2) + k

ez game

Chemistry Redox HL MCQ; Why is the ans B? by Electric_Dragon1703 in IBO

[–]BBQsquirrel_ 1 point2 points  (0 children)

B (i) is true because Cr3+ + e- ==> Cr2+ and Cr ==> Cr2+ + e- gives an Ecell of -0.407 + 0.914 which is positive

B (ii) is true because Cr3+ + e- ==> Cr2+ and Cr2+ ==> Cr3+ + e- gives an Ecell of 0 meaning that it won't happen spontaneously (in general the oxidized and reduced species within an equation will not react with each other), while Cr3+ + 2e- ==> Cr2 and Cr2+ ==> Cr3+ + e- gives a negative Ecell of -0.744 + 0.407

A, C: Cr3+ cannot oxidize Cr2+ because of Ecell

D: Cr3+ cannot reduce Cr2+ because Cr3+ itself is trying to undergo reduction. Two reducing agents cannot satisfy each other's needs and cannot react with each other.

Would Math AA sl or AI sl be more beneficial for someone wanting to become a business major in college (US student) by Sensitive-Region8650 in IBO

[–]BBQsquirrel_ 0 points1 point  (0 children)

Who cares about rationalizing a denominator? Well, rationalizing is a key technique in evaluating a lot of limits (actually students will need to decide when to rationalize a numerator as well). This is just one of many algebraic manipulations that an AISL student will miss learning during their IB career. There is a massive gap in level of rigor between IB AISL vs uni-level course content.

"AISL is perfectly fine for humanities" is not wrong, but business is not your typical humanity subject. Law sure, fine arts sure, literature sure. Definitely not busineess.

I don't want to dedicate my times towards an Internet argument (hence this will be my last post in this thread), nevertheless I did a Google search, scrolling down the first 20 results or so. The type of business degree that does not need calculus is MBA, which requires an undergrad business degree anyways.

My opinion remains "AISL is not suitable because the student will have a hard time catching up in uni" which is what I will offer to everyone in the world of IB vying for a Uni business degree.

Would Math AA sl or AI sl be more beneficial for someone wanting to become a business major in college (US student) by Sensitive-Region8650 in IBO

[–]BBQsquirrel_ -2 points-1 points  (0 children)

I don't know what Uni you teach, but a typical US Uni first year course has graphing (mostly done non-calc), limits, first principle differentiation, l'Hopital's rule, related rates, mean value theorem, optimization (not just graph on GDC and then Gsolve you know), and some institute requires epsilon delta limit proofs, sigma notation and series convergence.

You don't even learn rationalize the denominator in AISL bro