化简并求值3a+abc-1/3c^2-3a+1/3c^2,其中a=-1/6,b=2,

问题描述:

化简并求值3a+abc-1/3c^2-3a+1/3c^2,其中a=-1/6,b=2,

3a+3ac-(1/3)c^2-3a+(1/3)c^2
=(3a-3a)+(1/3c^2-1/3c^2)+abc
=abc
a=-1/6;b=2;c=-3
原式=abc=(-1/6)*2*(-3)=1;

3的平方-3p+15=0
9-3p+15=0
3p=15+9
3p=24
p=24÷3
p=8另一边是2a-b-(a-b)
=2a-b-a+b
=3a
周长=2[(2a-b)+3a]
=2(5a-b)
=10a-2b

3a+abc-1/3c^2-3a+1/3c^2
=(3a-3a)+abc+(1/3c^2-1/3c^2)
=abc
=1