dfrac (3)(2) D. dfrac (1)(2)

-dfrac (2)(3) C. dfrac (2)(3) D. dfrac (1)(9)

((y+dfrac {1)(2))}^2=dfrac (3)(4) D. ((y-dfrac {1)(2))}^2=dfrac (3)(4)

_(1)-(F)_(2)-|||-C. dfrac (2)(3)(F)_(1)+dfrac (1)(3)(F)_(2)-|||-D. dfrac (2)(3)(

B. dfrac {1)(2) . C. dfrac (2)(3) . D. dfrac (3)(4)

dfrac (1)(6)-|||-C. dfrac (1)(2) D. dfrac (1)(3)

dfrac (1)(6)-|||-C. dfrac (1)(2) D. dfrac (1)(3)

dfrac (1)(x) C. -dfrac (1)({x)^2} D. dfrac (2)({x)^3}

dfrac (3)(2)RC dfrac (7)(2)R D. dfrac (3)(2)RT对于双原子气体的摩尔定压热容的表达式为()

dfrac (7)(2) D. dfrac (9)(2)

已知_(1)=((dfrac {1)(3),-dfrac (2)(3),-dfrac (2)(3))}^T, _(2)=((-dfrac {2)(3),dfra