[DOC] add faq on simple data forecast

nbs/docs/getting-started/5_faq.ipynb

@@ -366,6 +366,22 @@
     "</details>"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "<details>\n",
+    "    <summary>Can TimeGPT forecast data with simple pattern such as a straight line or sine wave?</summary>\n",
+    "\n",
+    "While this is not the primary use case for `TimeGPT`, it is capable of generating solid results on simple data such as a straight line. While zero-shot predictions might not always meet expectations, a little help with fine-tuning allows TimeGPT to quickly grasp the trend and produce accurate forecasts. For more details, please refer to the [Improve Forecast Accuracy with TimeGPT](https://docs.nixtla.io/docs/tutorials-improve_forecast_accuracy_with_timegpt) tutorial.\n",
+    "<video controls width=\"600\">\n",
+    "        <source src=\"../../assets/forecast_synthetic_data.mp4\" type=\"video/mp4\">\n",
+    "        Your browser does not support the video tag.\n",
+    "    </video>\n",
+    "\n",
+    "</details>"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},