To find the missing term in the product \((−9m^6+12m^5)(m^2+2m+1)=−9m^8−6m^7+?+12m^5\), we first expand the left-hand side.
Given: \[ A = -9m^6 + 12m^5 \] \[ B = m^2 + 2m + 1 \]
Now, let's perform the multiplication \(A \cdot B\):
\[ A \cdot B = (-9m^6)(m^2) + (-9m^6)(2m) + (-9m^6)(1) + (12m^5)(m^2) + (12m^5)(2m) + (12m^5)(1) \]
Calculating each term:
- \((-9m^6)(m^2) = -9m^8\)
- \((-9m^6)(2m) = -18m^7\)
- \((-9m^6)(1) = -9m^6\)
- \((12m^5)(m^2) = 12m^7\)
- \((12m^5)(2m) = 24m^6\)
- \((12m^5)(1) = 12m^5\)
Now we will combine like terms:
- The \(m^8\) term is \(-9m^8\).
- The \(m^7\) terms are \(-18m^7 + 12m^7 = -6m^7\).
- The \(m^6\) terms are \(-9m^6 + 24m^6 = 15m^6\).
- The \(m^5\) term is \(12m^5\).
Thus, the overall product is: \[ -9m^8 - 6m^7 + 15m^6 + 12m^5 \]
Now we compare this to the given expression: \[ −9m^8−6m^7+?+12m^5 \]
We can see that the missing term, which we have calculated as \(15m^6\), should be represented as \(?\).
Thus, the missing term is: \[ \boxed{15m^6} \]