问题
选择题
x10=a0+a1(x-1)+a2(x-1)2+…+a10(x-1)10,则a7的值为( )
A.-120
B.45
C.120
D.-45
答案
因为x10=[(x-1)+1]10=a0+a1(x-1)+a2(x-1)2+…+a10(x-1)10,
所以a7=C103=120
故选C.
x10=a0+a1(x-1)+a2(x-1)2+…+a10(x-1)10,则a7的值为( )
A.-120
B.45
C.120
D.-45
因为x10=[(x-1)+1]10=a0+a1(x-1)+a2(x-1)2+…+a10(x-1)10,
所以a7=C103=120
故选C.