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A.1              B.-1             C.              D.

(1);

(2)sin²(-α)+tan(2π+α)·cos²(π+α)-sin(2π-α)·cos(π-α)-.

A.sin(-α-π)=sinα                            B.sin(π-α)=-sin(-α-π)

C.cos(-α+β)=-cos(α-β)                   D.cos(-α+β)=cos(α+β)

A.5-                                 B.-5

C.4                                        D.-4

A.                B.－              C.            D.±

A.tannα             B.-tannα             C.tanα             D.-tanα

A.(3+)                          B.(3-)

C.(1-)                           D.(1+)