问题
解答题
计算: (1)cos245°+tan60°•sin60°-2tan45°sin30°; (2)(sin45°-π)0-2|-cos60°|-
|
答案
(1)原式=(
)2+2 2
×3
-2×1×3 2 1 2
=
+1 2
-13 2
=2-1
=1;
(2)原式=1-2×
-21 2
+3 3
=1-1-2
+3 3
=-
.3
计算: (1)cos245°+tan60°•sin60°-2tan45°sin30°; (2)(sin45°-π)0-2|-cos60°|-
|
(1)原式=(
)2+2 2
×3
-2×1×3 2 1 2
=
+1 2
-13 2
=2-1
=1;
(2)原式=1-2×
-21 2
+3 3
=1-1-2
+3 3
=-
.3