Derivatives of the six trigonometric functions with examples

The six trig functions have a short list of derivative rules. Let’s put them in one place, then use them in examples that also need the power rule and product rule.

Use the six trig derivative rules

These rules use radians and apply wherever the original function is defined. In sin(x), the x is the input to sine. A coefficient in front, like the 4 in 4cos(x), stays as a multiplier when we differentiate.

Trigonometric functions and their derivatives
FunctionDerivative
sin(x)cos(x)
cos(x)-sin(x)
tan(x)sec2(x)
cot(x)-csc2(x)
sec(x)sec(x)tan(x)
csc(x)-csc(x)cot(x)

Keep the constant and differentiate term by term

For y=4cos(x), the derivative is 4 times the derivative of cosine, or -4sin(x). For y=8x5-9cot(x), use the power rule on the first term and the cotangent rule on the second.

y′=8(5)x4-9(-csc2(x))y′=40x4+9csc2(x)

Use the product rule when a term has two factors

Let y=sec(x)-7x5sin(x)+3csc(x)cos(x). The derivative of sec(x) is sec(x)tan(x). For -7x5sin(x), differentiate each factor once, keeping the other factor in place.

(-35x4)sin(x)+(-7x5)cos(x)

For 3csc(x)cos(x), the product rule gives -3csc(x)cot(x)cos(x)-3csc(x)sin(x). Since csc(x)cos(x)=cot(x) and csc(x)sin(x)=1 on this domain, it simplifies to -3cot2(x)-3. Now combine the three derivatives.

y′=sec(x)tan(x)-35x4sin(x)-7x5cos(x)-3cot2(x)-3