问题
解答题
(1)(x+3)3+27=0 (2)216-8x3=-127 (3)|
(4)
|
答案
(1)移项得,(x+3)3=-27,
开立方得,x+3=-3,
解得,x=-6;
(2)移向得,-8x3=-127-216,
合并同类项得,-8x3=-343,
系数化为1得,x3=
,343 8
开立方得,x=
;7 8
(3)原式=
-3
+22 2
=
+3
;2
(4)原式=2+
-1-2
-12
=0.