fix: math fixed

Author: cosmic-cortex

docs/source/content/examples/bayesian_optimization.ipynb

@@ -100,8 +100,8 @@
    "source": [
     "## Optimizing using *expected improvement*\n",
     "During the optimization, the utility of each point is given by the so-called *acquisition function*. In this case, we are going to use the *expected improvement*, which is defined by\n",
-    "<p align=\"center\">$$ EI(x) = (\\mu(x) - f(x^+)) \\psi\\Big( \\frac{\\mu(x) - f(x^+)}{\\sigma(x)} \\Big) + \\sigma(x) \\phi\\Big( \\frac{\\mu(x) - f(x^+)}{\\sigma(x)} \\Big), $$ </p>\n",
-    "where $ \\mu(x) $ and $ \\sigma(x) $ are the mean and variance of the Gaussian process regressor at $ x $, $ f $ is the function to be optimized with estimated maximum at $ x^+ $, and $ \\psi(z) $, $ \\phi(z) $ denotes the cumulative distribution function and density function of a standard Gaussian distribution. After each query, the acquisition function is reevaluated and the new query is chosen to maximize the acquisition function. "
+    "$$EI(x) = (\\mu(x) - f(x^+)) \\psi\\Big( \\frac{\\mu(x) - f(x^+)}{\\sigma(x)} \\Big) + \\sigma(x) \\phi\\Big( \\frac{\\mu(x) - f(x^+)}{\\sigma(x)} \\Big),$$\n",
+    "where $\\mu(x)$ and $\\sigma(x)$ are the mean and variance of the Gaussian process regressor at $x$, $f$ is the function to be optimized with estimated maximum at $x^+$, and $\\psi(z)$, $\\phi(z)$ denotes the cumulative distribution function and density function of a standard Gaussian distribution. After each query, the acquisition function is reevaluated and the new query is chosen to maximize the acquisition function. "
    ]
   },
   {