求(1÷sin10÷sin10-1÷cos10÷cos10)÷cos20

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/04 14:51:55
求(1÷sin10÷sin10-1÷cos10÷cos10)÷cos20

求(1÷sin10÷sin10-1÷cos10÷cos10)÷cos20
求(1÷sin10÷sin10-1÷cos10÷cos10)÷cos20

求(1÷sin10÷sin10-1÷cos10÷cos10)÷cos20
原式=(cos²10/sin²10cos²10-sin²10/sin²10cos²10)÷cos20
=(cos²10-sin²10)/sin²10cos²10÷cos20
=cos20/sin²10cos²10÷cos20
=1/sin²10cos²10
如果还要化简的话
继续=1/(sin10cos10)²
=1/(sin20/2)²
=4/sin20