Explanation: 
Another Explanation (5):
দেওয়া আছে, \( f(y) = y^3 + ay^2 - 6y - 12 \)
\( f(-2) = 0 \) হলে, \( a \) এর মান নির্ণয় করতে হবে।
\( f(-2) = (-2)^3 + a(-2)^2 - 6(-2) - 12 \)
\( \implies 0 = -8 + 4a + 12 - 12 \)
\( \implies 0 = -8 + 4a \)
\( \implies 4a = 8 \)
\( \implies a = \frac{8}{4} \)
\( \implies a = 2 \)
অতএব, \( a = 2 \) হলে \( f(-2) = 0 \) হবে। 🎉