Ta có:B=\(\left(x^{2007}+3x^{2006}-1\right)^{2007}\)
\(\Rightarrow\)B=\(\left(\left(-3\right)^{2007}+3\times\left(-3\right)^{2006}-1\right)^{2007}\)
B=\(\left(\left(-3\right)\times\left(-3\right)^{2006}+3\times\left(-3\right)^{2006}-1\right)^{2007}\)
B=\(\left(\left(\left(-3\right)+3\right)\times\left(-3\right)^{2006}-1\right)^{2007}\)
B=\(\left(0\times\left(-3\right)^{2006}-1\right)^{2007}\)
B=\(\left(0-1\right)^{2007}\)
B=\(\left(-1\right)^{2007}\)
B=\(\left(-1\right)\)