问题
解答题
(1)计算:6tan230°-
(2)解方程:4x2-5x-2=0. |
答案
(1)原式=6×(
)2-3 3
×3
-2×3 2 2 2
=
-1 2
,2
(2)原式可化简为(x-
)2-5 2
=0,33 4
解得:x1=
,x2=
+533 2
.
-533 2
(1)计算:6tan230°-
(2)解方程:4x2-5x-2=0. |
(1)原式=6×(
)2-3 3
×3
-2×3 2 2 2
=
-1 2
,2
(2)原式可化简为(x-
)2-5 2
=0,33 4
解得:x1=
,x2=
+533 2
.
-533 2