问题
选择题
(x+1)2+(x+1)11=a0+a1(x+2)+a2(x+2)2+…+a10(x+2)10+a11(x+2)11,则a1=( )
A.-12
B.-10
C.9
D.11
答案
(x+1)2+(x+1)11=[(x+2)-1]2+[(x+2)-1]11,
则a1=
(-1)+C 12
(-1)10=-2+11=9,C 1011
故选C.
(x+1)2+(x+1)11=a0+a1(x+2)+a2(x+2)2+…+a10(x+2)10+a11(x+2)11,则a1=( )
A.-12
B.-10
C.9
D.11
(x+1)2+(x+1)11=[(x+2)-1]2+[(x+2)-1]11,
则a1=
(-1)+C 12
(-1)10=-2+11=9,C 1011
故选C.