问题
解答题
计算: (1)2sin260°-tan45°+cos30°-tan30°; (2)
|
答案
(1)原式=2×(
)2×1+3 2
×3 2
(1分)3 3
=
+3 2
(2分)1 2
=2.(3分)
(2)原式=
(1分)3× 1 2 5×
-11 2
=
(2分)3 2
-15 2
=1.(3分)
计算: (1)2sin260°-tan45°+cos30°-tan30°; (2)
|
(1)原式=2×(
)2×1+3 2
×3 2
(1分)3 3
=
+3 2
(2分)1 2
=2.(3分)
(2)原式=
(1分)3× 1 2 5×
-11 2
=
(2分)3 2
-15 2
=1.(3分)