Question

先化简在求值1/3(-3ax的平方-ax+3)+ax的平方+1/2ax+1,其中a=-2,x=3

Answer 1

1/3(-3ax的平方-ax+3)+ax的平方+1/2ax+1,
=-ax²-1/3ax+1+ax²+1/2ax+1
=1/6ax+1
=1/6x(-2)x3+1
=-1+1
=0

Answer 2

1/3(-3ax²-ax+3)+ax²+1/2ax+1
=1/3×【-3×（-2）×3²-（-2）×3+3】+（-2）×3²+1/2×（-2）×3+1
=1/3×【6×9+2×3+3】+（-2）×9+（-3）+1
=1/3×【54+6+3】+（-18）-3+1
=1/3×63-18-3+1
=21-18-3+1
=1