diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json
index b49c492..b40bfa0 100644
--- a/.obsidian/workspace.json
+++ b/.obsidian/workspace.json
@@ -11,9 +11,11 @@
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+                "file": "4a1s/RAS/T - Aula 3.md",
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@@ -83,7 +85,7 @@
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@@ -100,7 +102,7 @@
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-                "file": "Excalidraw/doodles.excalidraw.md",
+                "file": "4a1s/RAS/T - Aula 3.md",
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@@ -123,7 +125,7 @@
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+                "file": "4a1s/RAS/T - Aula 3.md"
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@@ -157,8 +159,9 @@
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@@ -183,7 +186,6 @@
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     "4a1s/Excalidraw/ASCN/multi-tier.excalidraw.md",
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-    "4a1s/Excalidraw/ASCN/master.excalidraw.md",
     "-.32118",
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diff --git a/4a1s/RAS/T - Aula 3.md b/4a1s/RAS/T - Aula 3.md
new file mode 100644
index 0000000..1e0b689
--- /dev/null
+++ b/4a1s/RAS/T - Aula 3.md	
@@ -0,0 +1,9 @@
+26 de Setembro 2023 - #RAS 
+
+## Definition of Requirements Engineering
+- **Requirements engineering** designates all the activities related to requirements discovery, negotiation, documentation, and maintenance.
+- Alternative designation: analysis
+
+>[!hint]+ Zave, 1997
+>Requirements engineering, in the scope of software engineering, is focused on the real-world objectives established for the functionalities and the restrictions of software systems.
+