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Reference · Formulas

Derivative Rules

The core differentiation rules plus common derivatives — browse, filter, and copy.

Click any rule to copy it.

A function (x²) and its derivative (2x) — the derivative is the slope
The curve f(x) = x squared and its derivative f′(x) = 2x. The derivative line gives the slope of the function at each point: negative where the parabola falls, zero at its minimum, and positive where it rises.9−6x = −3x = 3
f(x) = x²f′(x) = 2x

The core differentiation rules are the constant, power, constant-multiple, sum/difference, product, quotient, and chain rules. The power rule gives d/dx (xⁿ) = n·xⁿ⁻¹, and the chain rule handles compositions: d/dx f(g(x)) = f′(g(x))·g′(x). Combine these with the standard trig, exponential, and log derivatives to differentiate almost any function.

How the rules fit together

Differentiation is built from a small set of rules applied in layers. The power rule handles polynomials; the sum, constant-multiple, product, and quotient rules combine simpler pieces; and the chain rule wraps around any composition. Once you know the derivatives of the elementary functions — powers, sine and cosine, eˣ, and ln x — every other derivative follows by assembling these rules in the right order.

The elementary derivatives to memorise

A handful of standard results appear again and again: d/dx sin x = cos x, d/dx cos x = −sin x, d/dx eˣ = eˣ, and d/dx ln x = 1/x. The trigonometric derivatives come in matched pairs, and the co-functions (cos, cot, csc) all carry a leading minus sign. Keep the signs straight and the rest is bookkeeping.

Core differentiation rules

The seven structural rules that combine simpler derivatives.

RuleFormula
Constantd/dx (c) = 0
Powerd/dx (xⁿ) = n·xⁿ⁻¹
Constant multipled/dx (c·f) = c·f′
Sum / difference(f ± g)′ = f′ ± g′
Product(f·g)′ = f′g + f g′
Quotient(f/g)′ = (f′g − f g′) / g²
Chaind/dx f(g(x)) = f′(g(x))·g′(x)

Common derivatives

Elementary functions — trigonometric, exponential, logarithmic, and inverse trig.

FunctionDerivative
sin xcos x
cos x−sin x
tan xsec²x
cot x−csc²x
sec xsec x tan x
csc x−csc x cot x
aˣ ln a
ln x1/x
logₐ x1 / (x ln a)
arcsin x1 / √(1−x²)
arccos x−1 / √(1−x²)
arctan x1 / (1+x²)

The chain rule is the key to composites

Most real-world functions are compositions — one function inside another — and the chain rule is what unlocks them. To differentiate f(g(x)), take the derivative of the outer function evaluated at the inner one, then multiply by the derivative of the inner function: f′(g(x))·g′(x). For example, d/dx sin(x²) = cos(x²)·2x. Whenever you see a function tucked inside sine, an exponential, a root, or a power, reach for the chain rule and work from the outside in.

What is the power rule?
The power rule states d/dx (xⁿ) = n·xⁿ⁻¹: bring the exponent down as a coefficient and reduce it by one. For example, d/dx (x³) = 3x². It works for any real exponent, including negatives and fractions.
When do I use the chain rule?
Use it whenever one function is nested inside another, such as sin(x²) or e^(3x). Differentiate the outer function at the inner one and multiply by the inner derivative: d/dx sin(x²) = cos(x²)·2x.
What is the correct order for the quotient rule?
For (f/g)′ the numerator is f′g − f g′, in that order, all over g². The order matters because subtraction is not commutative — swapping the terms flips the sign of the whole derivative.
Why isn’t the derivative of a product just f′·g′?
Because a product’s rate of change has two contributions: f changing while g holds, and g changing while f holds. The product rule adds them: (f·g)′ = f′g + f g′, not the product of the two derivatives.
Why do cos, cot, and csc derivatives carry a minus sign?
The three co-functions decrease where their partners increase, so their derivatives pick up a leading minus: d/dx cos x = −sin x, d/dx cot x = −csc²x, and d/dx csc x = −csc x cot x.
What is the difference between the derivatives of eˣ and aˣ?
The function eˣ is its own derivative because ln e = 1. A general base gives d/dx aˣ = aˣ ln a, so the extra factor ln a appears for every base other than e.