Find \((f\circ g)(-2)\)
📝 Question
Let:
\[ f(x)=x^2+x+1,\quad g(x)=1-x^2 \]
Find \((f\circ g)(-2)\).
✅ Solution
🔹 Step 1: Use definition
\[ (f\circ g)(x)=f(g(x)) \] —
🔹 Step 2: Find \(g(-2)\)
\[ g(-2)=1-(-2)^2=1-4=-3 \] —
🔹 Step 3: Find \(f(g(-2))\)
\[ f(-3)=(-3)^2+(-3)+1 \] :contentReference[oaicite:0]{index=0} —
🎯 Final Answer
\[ \boxed{(f\circ g)(-2)=7} \]
🚀 Exam Shortcut
- Compute inner function first
- Then substitute into outer function
- Careful with signs