diff --git a/auditok/signal.py b/auditok/signal.py
index 4b088a6..db9e10c 100644
--- a/auditok/signal.py
+++ b/auditok/signal.py
@@ -90,7 +90,7 @@ def calculate_energy(x, agg_fn=None):
     The energy is calculated as:
 
     .. math::
-       \text{energy} = 20 \log\left(\sqrt{\frac{1}{N} \sum_{i=1}^{N} a_i^2}\right) % # noqa: W605
+       \\text{energy} = 20 \\log(\\sqrt({1}/{N} \\sum_{i=1}^{N} {a_i}^2))  % # noqa: W605
 
     where `a_i` is the i-th audio sample and `N` is the total number of samples
     in `x`.
diff --git a/auditok/util.py b/auditok/util.py
index 3f7e2e1..c13d648 100644
--- a/auditok/util.py
+++ b/auditok/util.py
@@ -260,7 +260,7 @@ class AudioEnergyValidator(DataValidator):
     as:
 
     .. math::
-        energy = 20 \log(\sqrt({1}/{N} \sum_{i=1}^{N} {a_i}^2))  % # noqa: W605
+        \\text{energy} = 20 \\log(\\sqrt({1}/{N} \\sum_{i=1}^{N} {a_i}^2))  % # noqa: W605
 
     where `a_i` represents the i-th audio sample.