A.                                                             B.9

C.                                                               D

A.2^－2k                                                              B.2^－(2k－1)

C.－2^－(2k+1)                                                     D.2

①=(m+n)；②(a⁴)=a³,a∈R；③函数y=(x+1)－(2x+1)⁰的定义域是(－1,  +∞)；④(a⁶b^－3)=ab²(a、b>0).

A.0                                                                 B.1

C.2                                                                 D.3

(1) =________；(2)=________.

A.(－2,2)                                                      B.(－∞,－2)∪(2,+∞)

C.{x∈R|x≠2且x≠－2}                                 D.R

下列等式中，不正确的是

A.=－3                                                B.=－25

C.=5                                                   D.=(a>0)

A.a¹⁶                                                               B.a⁸

C.a⁴                                                                D.a²

下列等式能够成立的是

A.()⁷=·m⁷(m≠n，m≠0)                      B.=

C.=(x≥0，y≥0)                 D.=

(1)÷÷；

(2)(x^－1+x+x⁰)；

(3)；

(4) (a³+a^－3)(a³－a^－3)÷［(a⁴+a^－4+1)(a－a^－1)］.