Answer:
a
Step-by-step explanation:
[tex]a_{1} = -6\\\\a_{n}=\frac{1}{2}a_{n-1} - n\\\\a_{2}=\frac{1}{2}a_{1}-2\\\\ = \frac{1}{2}*(-6)-2\\\\ = -3 - 2\\\\= -5\\\\a_{3}=\frac{1}{2}a_{2}-3\\\\= \frac{1}{2}*(-5)-3\\\\=\frac{-5}{2}-3\\\\= \frac{-5}{2}-\frac{3*2}{1*2}\\\\=\frac{-5}{2}-\frac{6}{2}\\\\=\frac{-11}{2}[/tex]
