问题
解答题
(1)|-2|+(-1)2011×(π-
(2)解方程:x2+3x-1=0. |
答案
(1)原式=2-1×1-2+4
=2-1-2+4
=3;
(2)这里a=1,b=3,c=-1,
∵△=9+4=13,
∴x=
,-3± 13 2
则x1=
,x2=-3+ 13 2
.-3- 13 2
(1)|-2|+(-1)2011×(π-
(2)解方程:x2+3x-1=0. |
(1)原式=2-1×1-2+4
=2-1-2+4
=3;
(2)这里a=1,b=3,c=-1,
∵△=9+4=13,
∴x=
,-3± 13 2
则x1=
,x2=-3+ 13 2
.-3- 13 2