Find \(f(f(x))\)

📝 Question

Let:

\[ f(x)=3x+2 \]

Find \(f(f(x))\).

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✅ Solution

🔹 Step 1: Write composition

\[ f(f(x))=f(3x+2) \] —

🔹 Step 2: Substitute into function

\[ f(f(x))=3(3x+2)+2 \] —

🔹 Step 3: Simplify

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🎯 Final Answer

\[ \boxed{f(f(x))=9x+8} \]

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🚀 Exam Shortcut

• Replace \(x\) by \(f(x)\)
• Simplify step by step
• Be careful with multiplication