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Topic Guides2025-04-107 min read

The Hardest A-Level Maths Topics Ranked (And How to Beat Them)

From integration by parts to differential equations — here are the topics that cost students the most marks, and how to stop that happening to you.

Why some topics are harder than others

Not all A-Level Maths topics are equal. Some are hard because they require new ways of thinking. Some are hard because they build on earlier topics you might have shaky foundations in. Some are hard because the exam question style is unintuitive.

Here are the topics that consistently cause the most dropped marks, and the targeted approach to each.

1. Integration (Year 2)

Why it's hard: There's no single algorithm. Each question requires you to spot which technique applies — substitution, by parts, partial fractions, or recognising a standard form.

How to beat it: Create a decision tree. Given any integral, what's the first thing you ask? (Is it a product of two functions → try by parts. Is there a function and its derivative → try substitution.) Drill this until it's automatic.

2. Differential Equations

Why it's hard: Combines integration with algebraic manipulation. One slip and the whole question unravels.

How to beat it: Separating variables is the foundation. Get that absolutely solid before moving to integrating factors. Never skip a step — every line must follow from the last.

3. Proof by Contradiction

Why it's hard: The structure is counter-intuitive. You start by assuming the opposite of what you want to prove.

How to beat it: Learn the three templates — proving irrationals are irrational, proving infinitely many primes, proving something can't be rational — and understand why the contradiction works in each case.

4. The Normal Distribution (Statistics)

Why it's hard: Students confuse standardising, finding probabilities, and working backwards. The table or calculator use trips people up under pressure.

How to beat it: Always draw the curve. Always. Label what you're finding. Then standardise systematically. The drawing prevents you losing track of which area you want.

5. Vectors in 3D (Year 2)

Why it's hard: The geometric intuition is harder to build in 3D. Dot products and angles between lines/planes feel abstract.

How to beat it: Force yourself to write out vectors component-by-component every time. Don't skip steps because you think you can see it. The algebra is what saves you when intuition fails.

The pattern

Every "hard" topic has a beatable structure. The mistake students make is doing questions without understanding the underlying logic — then when the question is slightly reworded, they're stuck.

Use Infinity Stars to generate 10 questions on each of these topics at Challenging difficulty. Don't stop until you're not surprised by any question type.

Apply what you've learned

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