Update app.py

app.py

@@ -631,7 +631,7 @@ Important: When writing mathematical expressions, use these formatting rules re
    - Use $ for inline math
    - Use $$ on separate lines for equations
    - Put each solution step on its own line in $$ $$
-   - DO NOT use \\begin{{aligned}} or similar environments
+   - DO NOT use backslah backslash begin{{aligned}} or similar environments
    - When writing questions involving currency expressed in dollars NEVER use the `$` symbol as it will be interepreted as math mode. ALWAYS write out the word dollars.
       * Example: 1000 dollars
    - Never use parentheses or brackets around expressions, just use the dollar signs