igni

Is precalculus hard?

Precalculus is hard for some students and manageable for others, and the difference is mostly algebra. If factoring, fractions with variables, exponents and function notation are automatic for you, precalculus is a step up but a fair one. If any of them are shaky, the course feels much harder than it is.

You don't have to guess which group you're in. Below are four problems, one for each skill. They take about two minutes in total.

12 sin2x − sin x − 1 = 0
2(2 sin x − 1)(sin x + 1) = 0
3sin x = 1/2 or sin x = −1
4x = π/6, 5π/6, 3π/2

All three answers are wrong, and the trigonometry is perfect. The mistake is on line 2, and it's a factoring slip from Algebra 1. See what happened.

Why it feels hard

Three things change at once

Moving from Algebra 2 to precalculus changes three things simultaneously, which is why the step up can feel steeper than any single topic explains.

It covers a lot of ground

Algebra 2 mostly stays with equations and functions. Precalculus moves through polynomial and rational functions, exponentials and logarithms, and a full run of trigonometry. Many courses add sequences, vectors or conic sections. You get less time on each topic before the next one starts.

It stops telling you which method to use

Earlier courses hand you a type of problem and a procedure for it. Precalculus gives you a problem and expects you to decide what applies. A trig equation might need factoring. A logarithm problem might need exponent rules from two years ago.

Every problem leans on earlier skills

The new idea in a precalculus problem is often one line. The other five lines are algebra. So when a line goes wrong, it is usually not the new idea that broke.

Two minutes

The four skills precalculus assumes

Your teacher won't re-teach these. Try each problem before you look at the answer, on paper or with igni checking your steps. If one takes more than a minute, or you get it wrong, that is the skill to fix first.

1. Factoring quadratics

You will factor inside trig equations, rational functions and polynomial problems all year.

Solve 2x2 − 5x − 3 = 0

Solve it with igni igni checks each step as you go. It won't give you the answer.

Show the answer

(2x + 1)(x − 3) = 0, so x = 3 or x = −1/2.

2. Fractions with variables

Rational functions are a whole unit, and trig identities are mostly fraction work.

Simplify (x2 − 9) / (x2 + 3x)

Solve it with igni igni checks each step as you go. It won't give you the answer.

Show the answer

Factor both parts: (x − 3)(x + 3) / [x(x + 3)]. The (x + 3) cancels, leaving (x − 3) / x, as long as x is not 0 or −3.

3. Exponent rules

Logarithms are exponents written another way, so weak exponent rules make the whole logarithm unit harder.

Simplify (8x6)2/3

Solve it with igni igni checks each step as you go. It won't give you the answer.

Show the answer

82/3 = 4 and (x6)2/3 = x4, so the result is 4x4.

4. Function notation

Precalculus is a course about functions: combining them, inverting them and transforming them.

If f(x) = x2 − 1 and g(x) = 2x + 3, find f(g(x))

Solve it with igni igni checks each step as you go. It won't give you the answer.

Show the answer

(2x + 3)2 − 1 = 4x2 + 12x + 9 − 1 = 4x2 + 12x + 8.

How to read your result.

Four easy ones: precalculus will be new material, not a wall.

One or two slow or wrong: you have a specific gap, and a few weeks of focused practice usually closes it.

Three or four: fix these before the trigonometry unit starts, because that is where they all get used at once.

A worked example

What it looks like when precalculus goes wrong

Here is a typical precalculus problem: solve 2 sin2x − sin x − 1 = 0 for x between 0 and 2π. A student writes this:

holds up2 sin2x − sin x − 1 = 0
check this(2 sin x − 1)(sin x + 1) = 0
follows from itsin x = 1/2 or sin x = −1
follows from itx = π/6, 5π/6, 3π/2

All three answers are wrong, and the trigonometry is perfect. The unit circle values on line 4 are exactly right for line 3.

The mistake is on line 2. The signs in the factoring are reversed. Multiply (2 sin x − 1)(sin x + 1) back out and you get 2 sin2x + sin x − 1, which is not the problem. Here is the same problem with that one line fixed:

holds up2 sin2x − sin x − 1 = 0
holds up(2 sin x + 1)(sin x − 1) = 0
holds upsin x = −1/2 or sin x = 1
holds upx = 7π/6, 11π/6, π/2

One sign on one line, three lines earlier than where the answer came out wrong.

That is an Algebra 1 skill breaking a precalculus problem. The student who sees three wrong answers concludes "I don't get trig equations". The truth is smaller and easier to fix: check the factoring by multiplying it back out.

This is the pattern behind most precalculus struggles. The new material gets the blame for an old mistake.

Compared with

Precalculus against the courses either side of it

Is precalculus harder than Algebra 2?

For most students, yes. It moves faster, covers more topics and adds trigonometry in depth. But much of the first semester revisits Algebra 2 ideas at a higher level, so a student who finished Algebra 2 with solid skills starts on familiar ground.

If Algebra 2 is the course you're in now, or the one that went badly, is Algebra 2 hard? has its own four checks — and they're the Algebra 1 skills underneath the four on this page.

Is precalculus harder than calculus?

It depends on the student, and plenty of students say precalculus felt harder. Calculus is built around a few connected ideas: limits, derivatives and integrals. Precalculus is a collection of separate topics, so there is more to keep track of.

The algebra and trigonometry from precalculus are also where most calculus mistakes happen, which is why doing precalculus properly pays off the following year.

Is precalculus harder than trigonometry?

Trigonometry is usually part of precalculus, often about half of it. Where trigonometry is taught as its own course, precalculus is the broader and more demanding of the two.

Is precalculus harder than statistics?

They are hard in different ways. Precalculus is heavy on algebra and symbol work. Statistics uses less algebra and asks for more reading, interpreting and explaining.

Students with strong algebra often find precalculus more comfortable, and students who prefer working with context and data often prefer statistics.

Is precalculus hard in high school or in college?

The content is much the same. The pace is not. A high school course usually runs a full year, with a teacher who sees you most days. A college course often fits the same material into one semester, with less class time and more work on your own.

If you are taking it in college, the four skills above matter even more, because there is less time to catch up.

What helps

How to make precalculus easier

Fix the gap you found, not everything

If the factoring problem was the slow one, do twenty factoring problems this week. That will help more than re-reading the current chapter. Three of the four checks above are algebra, so how to get better at algebra is usually the more specific place to aim.

Solve problems instead of watching them

Following a video or a worked solution feels like understanding. Being able to do it on a blank page is a different skill, and it only comes from doing it. More on that, and the research behind it, in why is math so hard.

Check each line, not just the final answer

In the example above, the mistake was on line 2 and the student found out on line 4. If you check as you go, you catch a mistake while you still remember what you were thinking. This is move three in our guide on how to get better at math.

Don't read a bad test as proof you can't do it

One sign error can turn a whole page wrong. That says something about one line, not about you. If tests are where it falls apart rather than the homework, that's a different problem with a different fix — see math anxiety and how confidence actually gets built.

Where igni fits

Checking every step, on the homework you already have

Checking your own work is hard, because you are using the same reasoning that made the mistake. That is the part igni does.

Work the problem the way you normally would — on paper, snapping each step as you go, or typed straight into igni. After each step, igni tells you whether that line holds up before you build on it.

You still do the math

igni doesn't hand you the answer. You solve it; igni points at the line that broke.

It follows your method

A valid route your textbook didn't teach gets confirmed rather than marked wrong.

The gap becomes visible

Mistakes that keep landing in the same place show you which earlier skill to fix.

holds up2 sin2x − sin x − 1 = 0
check this(2 sin x − 1)(sin x + 1) = 0

Caught at line two, not at three wrong answers two lines later. The method is right; the signs in the factoring aren't. Multiply it back out and you'll see it.

Related guides

Where to go next

Next step

Find out what's actually making precalculus hard for you

igni asks a few questions — what course you're taking, how you study, and when math started feeling hard — so it knows how to work with you.

Then it's step checking on the homework you already have, on paper or on screen. You still do the math — igni tells you which line stopped working.

Free 7-day trial

Answer the questions

Reading this for your child? Start with why your child is struggling with math.