问题
解答题
计算: ①sin45°-cos45°+tan30° ②
|
答案
①原式=
-2 2
+2 2 3 3
=
;3 3
②原式=2×
+13 2 2×
-3 2
×2 2 2
=
+13
-13
=(
+1)(3
+1)3 (
-1)(3
+1)3
=4+2 3 2
=2+
.3
计算: ①sin45°-cos45°+tan30° ②
|
①原式=
-2 2
+2 2 3 3
=
;3 3
②原式=2×
+13 2 2×
-3 2
×2 2 2
=
+13
-13
=(
+1)(3
+1)3 (
-1)(3
+1)3
=4+2 3 2
=2+
.3