AP Calculus AB and BC

Derivative Rules: The Complete Table

The core rules are constant (derivative 0), power (x^n to n x^(n-1)), constant multiple, sum, difference, product, quotient, and chain. On top are the six trig derivatives, the inverse trig derivatives, and the exponential and log rules. Pick a rule by the function's outermost operation.

How to pick the right rule

Choosing a derivative rule is a recognition task, not a guessing game. Look at the outermost operation: the last thing you would do if you plugged in a number. That single question routes you to the right rule almost every time. The table below maps what a function looks like to the rule it needs, and the sections after it give the formulas grouped so the patterns are easy to remember.

The one question that decides

Identify the outermost operation. A sum wants the sum rule, a product wants the product rule, a composition wants the chain rule. Only after that do you differentiate the inside pieces.

When the function looks likeUse this ruleWhy / watch for
A number alone, like 77 or π\piConstantA constant never changes, so its slope is 00.
A single power, like x5x^5 or x2x^{-2}PowerWorks for any real exponent, including negatives and roots.
Terms joined by ++ or -Sum and differenceDifferentiate each term on its own, then recombine.
A number times a function, like 4cosx4\cos xConstant multipleThe coefficient rides along: the derivative is 4sinx-4\sin x.
Two functions multipliedProductNot fgf'g': each factor pairs with the other's derivative.
One function over anotherQuotientFirst check whether a rewrite turns it into a sum of powers.
A function nested inside another, like sin(x2)\sin(x^2)ChainOutside derivative times inside derivative; keep the inside.

These are Topics 2.5, 2.6, 2.8, 2.9, and 3.1 in the CED. The trig, inverse trig, exponential, and log rows below plug into these structural rules: whenever an inside function is more than a bare xx, the chain rule multiplies by that inside function's derivative.

Structural rules (Topics 2.5, 2.6, 2.8, 2.9, 3.1)

These seven rules combine or transform other functions. They are the scaffolding: the specific function derivatives in the later tables get fed into them.

RuleFormulaWhen to use it
Constantddx[c]=0\dfrac{d}{dx}[c] = 0A number standing alone. Its rate of change is zero.
Powerddx[xn]=nxn1\dfrac{d}{dx}[x^{n}] = n x^{n-1}Any single power of xx, including negative and fractional exponents. The workhorse for polynomials and radicals.
Constant multipleddx[cf(x)]=cf(x)\dfrac{d}{dx}[c\cdot f(x)] = c\cdot f'(x)A numeric coefficient on a function. Differentiate the function and keep the coefficient out front.
Sum and differenceddx[f±g]=f±g\dfrac{d}{dx}[f \pm g] = f' \pm g'A function written as terms joined by ++ or -. Handle each term separately.
Productddx[fg]=fg+fg\dfrac{d}{dx}[fg] = f'g + fg'Two nonconstant functions multiplied. The two terms are added, so their order is free.
Quotientddx[fg]=gffgg2\dfrac{d}{dx}\left[\dfrac{f}{g}\right] = \dfrac{g f' - f g'}{g^{2}}One function divided by another when the bottom is not a single power. Order is fixed: the gfg f' term comes first.
Chainddx[f(g(x))]=f(g(x))g(x)\dfrac{d}{dx}\big[f(g(x))\big] = f'(g(x)) \cdot g'(x)A composition, one function inside another. Multiply the outside derivative by the inside derivative.

The two most common slips

The product rule is fg+fgf'g + fg', never fgf'g'. The quotient rule subtracts in a fixed order, and reversing the two numerator terms flips the sign of the whole answer.

The six trigonometric derivatives (Topics 2.7 and 2.10)

Sine and cosine are the two you memorize outright (Topic 2.7). The other four come from rewriting tangent, cotangent, secant, and cosecant with identities and differentiating (Topic 2.10). All six formulas below assume the angle is in radians.

FunctionDerivativeWhy / when
sinx\sin xcosx\cos xMemorize directly; the anchor for the rest.
cosx\cos xsinx-\sin xA co-function, so its derivative carries a minus sign.
tanx\tan xsec2x\sec^{2} xFrom the quotient rule on sinx/cosx\sin x / \cos x.
cotx\cot xcsc2x-\csc^{2} xCo-function of tangent; note the minus sign.
secx\sec xsecxtanx\sec x \tan xFrom the chain rule on (cosx)1(\cos x)^{-1}.
cscx\csc xcscxcotx-\csc x \cot xCo-function of secant; carries a minus sign.

Two patterns that cut the memorizing in half

Every co-function (cosine, cotangent, cosecant) has a derivative that carries a minus sign. And when the angle is a function of xx rather than a bare xx, the chain rule tacks on the inside derivative: ddx[sinu]=cosuu\dfrac{d}{dx}[\sin u] = \cos u \cdot u'.

Inverse trig, exponential, and log derivatives (Topics 2.7 and 3.4)

The exponential and log rules for exe^{x} and lnx\ln x are Topic 2.7; the general bases axa^{x} and logax\log_a x come from them by rewriting. Notice how lna\ln a shows up as an extra factor whenever the base is not ee.

FunctionDerivativeWhy / when
exe^{x}exe^{x}Equal to its own derivative: every solution of f=ff' = f is CexCe^{x}.
axa^{x}axlnaa^{x} \ln aGeneral base: the extra factor is lna\ln a. When a=ea = e, lne=1\ln e = 1 recovers exe^{x}.
lnx\ln x1x\dfrac{1}{x}For x>0x > 0. Turns a logarithm into a simple power.
logax\log_a x1xlna\dfrac{1}{x \ln a}Change of base puts lna\ln a in the denominator.

The inverse trig derivatives (Topic 3.4) come from the inverse-function rule and the Pythagorean identities. AB and BC most often test arcsin\arcsin, arccos\arccos, and arctan\arctan; the other three are listed for completeness. The co-function pattern repeats: each co-inverse has the same size derivative as its partner but the opposite sign.

FunctionDerivativeWhy / when
arcsinx\arcsin x11x2\dfrac{1}{\sqrt{1-x^{2}}}Domain x<1|x| < 1. The inverse trig derivative AP uses most.
arccosx\arccos x11x2-\dfrac{1}{\sqrt{1-x^{2}}}Same size as arcsin\arcsin, opposite sign (co-function).
arctanx\arctan x11+x2\dfrac{1}{1+x^{2}}Defined for all xx; no radical, no sign trap.
arccotx\operatorname{arccot} x11+x2-\dfrac{1}{1+x^{2}}Co-function of arctan\arctan; opposite sign.
arcsecx\operatorname{arcsec} x1xx21\dfrac{1}{|x|\sqrt{x^{2}-1}}Domain x>1|x| > 1; keep the absolute value: dropping it flips the sign for x<1x < -1.
arccscx\operatorname{arccsc} x1xx21-\dfrac{1}{|x|\sqrt{x^{2}-1}}Co-function of arcsec\operatorname{arcsec}; opposite sign.

There is no formula sheet

The AP Calculus AB and BC exams provide no reference sheet, so every rule on this page has to be memorized or rebuilt quickly. With a chain rule, each inside function uu contributes a factor of uu': for example ddx[arctanu]=u1+u2\dfrac{d}{dx}[\arctan u] = \dfrac{u'}{1+u^{2}}.