化简:5(2x-3y)-2(3x-7y)
5(2x-3y)-2(3x-7y)
=10x-15y-6x+14y
=4x-y.
分解因式x4-1的结果为( )
A.(x2-1)(x2+1)
B.(x+1)2(x-1)2
C.(x-1)(x+1)(x2+1)
D.(x-1)(x+1)3
下列病症,不宜用三棱针治疗的是
A.高热惊厥
B.中风脱证
C.中暑昏迷
D.急性腰扭伤
E.喉蛾