(1)4a+b-3a-2b a=-2 ,b=-1 (2)3a+abc-1/2c的二次方,a=-1/6,b=2,c=-3.

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(1)4a+b-3a-2b a=-2 ,b=-1 (2)3a+abc-1/2c的二次方,a=-1/6,b=2,c=-3.

(1)4a+b-3a-2b a=-2 ,b=-1 (2)3a+abc-1/2c的二次方,a=-1/6,b=2,c=-3.
(1)4a+b-3a-2b a=-2 ,b=-1 (2)3a+abc-1/2c的二次方,a=-1/6,b=2,c=-3.

(1)4a+b-3a-2b a=-2 ,b=-1 (2)3a+abc-1/2c的二次方,a=-1/6,b=2,c=-3.
(1) 4a+b-3a-2b=(4a-3a)-(2b-b).
=a-b.
=(-2)-(-1)
=-2+1.
-1.
(2).3a+abc-(1/2)c^2=a(3+bc)-(1/2)c^2.
=(-1/6)[3+2*(-3)]-(1/2)*(-3)^2.
=(-1/6)*(-3)-9/2.
=1/2-9/2.
=-8/2.
=-4.