docs: add equations

lib/node_modules/@stdlib/math/base/special/cos/README.md

@@ -22,6 +22,22 @@ limitations under the License.
 
 > Compute the [cosine][cosine] of a number.
 
+<section class="intro">
+
+The [cosine][cosine] function can be expressed as the infinite series
+
+<!-- <equation class="equation" label="eq:cosine_function" align="center" raw="\cos(x) = \sum_{n=0}^{\infty} \frac{(-1)^n}{(2n)!} x^{2n} = 1 - \frac{x^2}{2!} + \frac{x^4}{4!} - \cdots" alt="Cosine function Taylor series expansion"> -->
+
+```math
+\cos(x) = \sum_{n=0}^{\infty} \frac{(-1)^n}{(2n)!} x^{2n} = 1 - \frac{x^2}{2!} + \frac{x^4}{4!} - \cdots
+```
+
+<!-- </equation> -->
+
+</section>
+
+<!-- /.intro -->
+
 <section class="usage">
 
 ## Usage

lib/node_modules/@stdlib/math/base/special/cosd/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [cosine][trigonometric-functions] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:cosine_degrees" align="center" raw="y = \cos\left(\frac{\pi x}{180}\right)" alt="Cosine of an angle in degrees"> -->
+
+```math
+y = \cos\left(\frac{\pi x}{180}\right)
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/cosdf/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [cosine][trigonometric-functions] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:cosine_degrees" align="center" raw="y = \cos\left(\frac{\pi x}{180}\right)" alt="Cosine of an angle in degrees"> -->
+
+```math
+y = \cos\left(\frac{\pi x}{180}\right)
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/cosf/README.md

@@ -22,6 +22,22 @@ limitations under the License.
 
 > Compute the [cosine][cosine] of a single-precision floating-point number (in radians).
 
+<section class="intro">
+
+The [cosine][cosine] function can be expressed as the infinite series
+
+<!-- <equation class="equation" label="eq:cosine_function" align="center" raw="\cos(x) = \sum_{n=0}^{\infty} \frac{(-1)^n}{(2n)!} x^{2n} = 1 - \frac{x^2}{2!} + \frac{x^4}{4!} - \cdots" alt="Cosine function Taylor series expansion"> -->
+
+```math
+\cos(x) = \sum_{n=0}^{\infty} \frac{(-1)^n}{(2n)!} x^{2n} = 1 - \frac{x^2}{2!} + \frac{x^4}{4!} - \cdots
+```
+
+<!-- </equation> -->
+
+</section>
+
+<!-- /.intro -->
+
 <section class="usage">
 
 ## Usage

lib/node_modules/@stdlib/math/base/special/cot/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [cotangent][trigonometric-functions] function is defined as
+
+<!-- <equation class="equation" label="eq:cotangent_function" align="center" raw="y = \cot(x) = \frac{\cos(x)}{\sin(x)}" alt="Cotangent function"> -->
+
+```math
+y = \cot(x) = \frac{\cos(x)}{\sin(x)}
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/cotd/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [cotangent][trigonometric-functions] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:cotangent_degrees" align="center" raw="y = \cot\left(\frac{\pi x}{180}\right)" alt="Cotangent of an angle in degrees"> -->
+
+```math
+y = \cot\left(\frac{\pi x}{180}\right)
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/cotdf/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [cotangent][trigonometric-functions] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:cotangent_degrees" align="center" raw="y = \cot\left(\frac{\pi x}{180}\right)" alt="Cotangent of an angle in degrees"> -->
+
+```math
+y = \cot\left(\frac{\pi x}{180}\right)
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/cotf/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [cotangent][trigonometric-functions] function is defined as
+
+<!-- <equation class="equation" label="eq:cotangent_function" align="center" raw="y = \cot(x) = \frac{\cos(x)}{\sin(x)}" alt="Cotangent function"> -->
+
+```math
+y = \cot(x) = \frac{\cos(x)}{\sin(x)}
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/csc/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [cosecant][trigonometric-functions] function is defined as
+
+<!-- <equation class="equation" label="eq:cosecant_function" align="center" raw="y = \csc(x) = \frac{1}{\sin(x)}" alt="Cosecant function"> -->
+
+```math
+y = \csc(x) = \frac{1}{\sin(x)}
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/cscd/README.md

@@ -22,6 +22,22 @@ limitations under the License.
 
 > Compute the [cosecant][cosecant] of a degree.
 
+<section class="intro">
+
+The [cosecant][cosecant] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:cosecant_degrees" align="center" raw="y = \csc\left(\frac{\pi x}{180}\right)" alt="Cosecant of an angle in degrees"> -->
+
+```math
+y = \csc\left(\frac{\pi x}{180}\right)
+```
+
+<!-- </equation> -->
+
+</section>
+
+<!-- /.intro -->
+
 <section class="usage">
 
 ## Usage

lib/node_modules/@stdlib/math/base/special/cscdf/README.md

@@ -22,6 +22,22 @@ limitations under the License.
 
 > Compute the [cosecant][cosecant] of a single-precision floating-point number (in degrees).
 
+<section class="intro">
+
+The [cosecant][cosecant] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:cosecant_degrees" align="center" raw="y = \csc\left(\frac{\pi x}{180}\right)" alt="Cosecant of an angle in degrees"> -->
+
+```math
+y = \csc\left(\frac{\pi x}{180}\right)
+```
+
+<!-- </equation> -->
+
+</section>
+
+<!-- /.intro -->
+
 <section class="usage">
 
 ## Usage

lib/node_modules/@stdlib/math/base/special/cscf/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [cosecant][trigonometric-functions] function is defined as
+
+<!-- <equation class="equation" label="eq:cosecant_function" align="center" raw="y = \csc(x) = \frac{1}{\sin(x)}" alt="Cosecant function"> -->
+
+```math
+y = \csc(x) = \frac{1}{\sin(x)}
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/sec/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [secant][trigonometric-functions] function is defined as
+
+<!-- <equation class="equation" label="eq:secant_function" align="center" raw="y = \sec(x) = \frac{1}{\cos(x)}" alt="Secant function"> -->
+
+```math
+y = \sec(x) = \frac{1}{\cos(x)}
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/secd/README.md

@@ -22,6 +22,22 @@ limitations under the License.
 
 > Compute the [secant][secant] of an angle measured in degrees.
 
+<section class="intro">
+
+The [secant][secant] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:secant_degrees" align="center" raw="y = \sec\left(\frac{\pi x}{180}\right) = \frac{1}{\cos\left(\frac{\pi x}{180}\right)}" alt="Secant of an angle in degrees"> -->
+
+```math
+y = \sec\left(\frac{\pi x}{180}\right) = \frac{1}{\cos\left(\frac{\pi x}{180}\right)}
+```
+
+<!-- </equation> -->
+
+</section>
+
+<!-- /.intro -->
+
 <section class="usage">
 
 ## Usage

lib/node_modules/@stdlib/math/base/special/secdf/README.md

@@ -22,6 +22,22 @@ limitations under the License.
 
 > Compute the [secant][secant] of a single-precision floating-point number (in degrees).
 
+<section class="intro">
+
+The [secant][secant] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:secant_degrees" align="center" raw="y = \sec\left(\frac{\pi x}{180}\right) = \frac{1}{\cos\left(\frac{\pi x}{180}\right)}" alt="Secant of an angle in degrees"> -->
+
+```math
+y = \sec\left(\frac{\pi x}{180}\right) = \frac{1}{\cos\left(\frac{\pi x}{180}\right)}
+```
+
+<!-- </equation> -->
+
+</section>
+
+<!-- /.intro -->
+
 <section class="usage">
 
 ## Usage

lib/node_modules/@stdlib/math/base/special/secf/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [secant][trigonometric-functions] function is defined as
+
+<!-- <equation class="equation" label="eq:secant_function" align="center" raw="y = \sec(x) = \frac{1}{\cos(x)}" alt="Secant function"> -->
+
+```math
+y = \sec(x) = \frac{1}{\cos(x)}
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/sin/README.md

@@ -22,6 +22,22 @@ limitations under the License.
 
 > Compute the [sine][sine] of a number.
 
+<section class="intro">
+
+The [sine][sine] function can be expressed as the infinite series
+
+<!-- <equation class="equation" label="eq:sine_function" align="center" raw="\sin(x) = \sum_{n=0}^{\infty} \frac{(-1)^n}{(2n+1)!} x^{2n+1} = x - \frac{x^3}{3!} + \frac{x^5}{5!} - \cdots" alt="Sine function Taylor series expansion"> -->
+
+```math
+\sin(x) = \sum_{n=0}^{\infty} \frac{(-1)^n}{(2n+1)!} x^{2n+1} = x - \frac{x^3}{3!} + \frac{x^5}{5!} - \cdots
+```
+
+<!-- </equation> -->
+
+</section>
+
+<!-- /.intro -->
+
 <section class="usage">
 
 ## Usage

lib/node_modules/@stdlib/math/base/special/sind/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [sine][trigonometric-functions] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:sine_degrees" align="center" raw="y = \sin\left(\frac{\pi x}{180}\right)" alt="Sine of an angle in degrees"> -->
+
+```math
+y = \sin\left(\frac{\pi x}{180}\right)
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/sindf/README.md

@@ -24,6 +24,16 @@ limitations under the License.
 
 <section class="intro">
 
+The [sine][trigonometric-functions] of an angle measured in degrees is computed as
+
+<!-- <equation class="equation" label="eq:sine_degrees" align="center" raw="y = \sin\left(\frac{\pi x}{180}\right)" alt="Sine of an angle in degrees"> -->
+
+```math
+y = \sin\left(\frac{\pi x}{180}\right)
+```
+
+<!-- </equation> -->
+
 </section>
 
 <!-- /.intro -->

lib/node_modules/@stdlib/math/base/special/sinf/README.md

@@ -22,6 +22,22 @@ limitations under the License.
 
 > Compute the [sine][sine] of a single-precision floating-point number (in radians).
 
+<section class="intro">
+
+The [sine][sine] function can be expressed as the infinite series
+
+<!-- <equation class="equation" label="eq:sine_function" align="center" raw="\sin(x) = \sum_{n=0}^{\infty} \frac{(-1)^n}{(2n+1)!} x^{2n+1} = x - \frac{x^3}{3!} + \frac{x^5}{5!} - \cdots" alt="Sine function Taylor series expansion"> -->
+
+```math
+\sin(x) = \sum_{n=0}^{\infty} \frac{(-1)^n}{(2n+1)!} x^{2n+1} = x - \frac{x^3}{3!} + \frac{x^5}{5!} - \cdots
+```
+
+<!-- </equation> -->
+
+</section>
+
+<!-- /.intro -->
+
 <section class="usage">
 
 ## Usage