若x2+kxy+16y2能用完全平方公式分解因式,则k的值为( )
A.4
B.-8
C.4或-4
D.8或-8
∵x2+kxy+16y2能用完全平方公式分解因式,
∴k=±8.
故选D.
My brother has been preparing carefully for the English exam, so that he can be sure of passing it at his
first _____. [ ]
A. request
B. attempt
C. promise
D. purpose
为了考虑固结程度和排水条件对抗剪强度的影响,根据加荷速率的快慢将直剪试验划分为()、()和()三种试验类型。