I like apples, ____________ I don't like pears.[ ]
A. and
B. to
C. but
D. in
答案:C
设函数f(x)=x2-6x,则f(x)在x=0处的切线斜率为( )
A.0
B.-1
C.3
D.-6
男性,22岁。跌倒后右膝疼痛,X线检查未见明显骨折。查体除内侧副韧带处明显压痛及肿胀外,无其他阳性体征。初步诊断为右膝内侧副韧带挫裂伤。最合适的治疗为()
A.手术
B.牵引
C.推拿及理疗
D.局封
E.石膏外固定