I read through the A-Level Maths Examiners' Reports, so you don't have to! In this video I go through the most common mistakes highlighted in those reports, as well as some from my ten years of teaching experience.
Let me know in the commons any other misconceptions you think are worth highlighting! Good luck with your exams 🍀
You may also find the "Content specification and marking guidance" section of this FAQ page helpful: https://support.pearson.com/uk/s/arti...
Specific wording in the 2022 report regarding the sinacosa vs cosasina part of the video: "There were a number of printed answers to show on this paper, and candidates must ensure that they show sufficient detail in their working to warrant being awarded all of the marks available and that they end up with exactly what is printed on the question paper. There were many cases where it was similar but not exactly as printed. Candidates run the risk of losing a mark in such cases."
Files used in the video saved here: https://drive.google.com/drive/folder...
I read through the A-Level Maths Examiners' Reports, so you don't have to! In this video I go through the most common mistakes highlighted in those reports, as well as some from my ten years of teaching experience.
Let me know in the commons any other misconceptions you think are worth highlighting! Good luck with your exams 🍀
You may also find the "Content specification and marking guidance" section of this FAQ page helpful: https://support.pearson.com/uk/s/arti...
Specific wording in the 2022 report regarding the sinacosa vs cosasina part of the video: "There were a number of printed answers to show on this paper, and candidates must ensure that they show sufficient detail in their working to warrant being awarded all of the marks available and that they end up with exactly what is printed on the question paper. There were many cases where it was similar but not exactly as printed. Candidates run the risk of losing a mark in such cases."
Files used in the video saved here: https://drive.google.com/drive/folder...
ur calc to solve polynomials,
solve using algabraic division or the quadratic formula
2) show the process of rationalising denominators. calculators may automatically
rationalise stuff, but u must still write it down to get the method mark
3) When finding an inverse function, ALWAYS write its domain. The question
may not always ask you to state the domain, but the mark scheme will still
want you to state it.
4) When calculating partial fractions, it's not enough to just find the variables.
you must write a final statement, expressing the fraction as an actual partial
fraction
5) When expressing a final answer, write it EXACTLY as it is written in the question.
eg if the question is "Show that ..... = U² sinθ cosθ", you may NOT get a mark
for writing it as "U² cosθ sinθ". You must write it exactly as printed.
6) Don't forget to write units. If it says "giving your answer to the nearest cm",
write the units. (modelling questions)
7) Give your answer to the correct number of decimal places.
if it says "giving your answer to 3 decimal places"... then give your answer
to 3 decimal places.
8) (modelling) Ensure you've expressed answers with the correct variable names.
If the question is "express H in terms of t", don't write the final answer in terms
of y or x.
9) (modelling) When it says "State one further refinement to the model", you CAN give
more than one example, BUT all of your examples must be correct otherwise
you lose the mark. Only write one answer, which you think is the best.
10) (mechanics) in SUVAT questions, (eg find the acceleration), your
final answer must be expressed to two/three sig figs. do not express the final
answer in terms of g or as a fraction (UNLESS the question asks for an exact value)
Misconceptions:
1) When showing a function has a root in an interval, where there is a change in sign,
you MUST state that f(x) is continuous along with stating the change in sign
2) when proving points of inflection, along with showing that the first
derivative is 0, you must show that the second derivative has a sign change (
ie f(x) changes from concave to convex or vice versa)
3) when solving equations, cancelling out terms, means that the term you
cancelled out can also equal 0.
eg, solve sinθcosθ = 3cos²θ
if you divide by cosθ, then cosθ = 0 is also possible.
4) if you have ∫sin²x dx, IT IS NOT EQUAL TO ⅓sin³x.
You must use the cos2x identity where cos2x = 1-2sin²x, rearranging for sin²x
5) Small angle approximation: cos3θ is equal to 1-(3θ)²/2, NOT 3(θ²)/2
6) 1-(1-5) is equal to 5, NOT -5.
1-(1-5)
= 1 -1(1-5)
= 1-1+5
= 5
7) x² + 16 = y². YOU CAN NOT SQUARE ROOT THE EQUATION TO GET x+16=y. IT IS NOT
THE SAME. you need to take the square root of the entire side.
so root(x²+16) = y.
In essence, "3² + 4² = 5²" rooted IS NOT "3 + 4 = 5"
likewise, if you have "y + eˣ = 4", if you want to ln both sides,
it IS NOT "lny + x = ln4".
You need to ln the entire side together, so it would actually be
ln(y + eˣ) = ln4
8) ln5/ln4 IS NOT ln5-ln4.
ln(5/4) IS ln5-ln4.
9) in binomial, when factorising out, make sure you apply the power.
eg, (4+x)^¹/² = 4^¹/² (4+x)^¹/². Don't forget to apply the power to the 4 that was
factorised out.
10) Don't confuse inverse functions with the first derivative of a function
inverse: f⁻¹(x)
differentiate: f'(x) [dash instead of -1]
11) Hypothesis testing - DO NOT WRITE "H₁=...."
It must be "H₁: ...." (USE A COLON INSTEAD OF THE EQUAL SIGN)
12) Hypothesis testing for correleation - use the greek letter ρ instead of r.
Ie "H₁: ρ>..."