问题
解答题
计算:tan30°•sin60°+cos230°-sin245°•tan45°.
答案
原式=
×3 3
+(3 2
)2-(3 2
)2×12 2
=
+1 2
-3 4
=1 2
.3 4
计算:tan30°•sin60°+cos230°-sin245°•tan45°.
原式=
×3 3
+(3 2
)2-(3 2
)2×12 2
=
+1 2
-3 4
=1 2
.3 4