ĐỀ THAM KHẢO KIỂM TRA 1 TIẾT CHƯƠNG I_ HÌNH HỌC 9

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ĐỀ THAM KHẢO KIỂM TRA 1 TIẾT CHƯƠNG I_ HÌNH HỌC 9

Bài 1 :(2 Điểm ) Không sử dụnng máy tính , hãy sắp xếp các tập số lượng giác sau theo thứ tự tăng d n

sin250,cos480, sin 750, cos620,sin 480

Bài 2 :(3 Điểm ) a)Không sử dụng máy tính ,hãy tính giá trị biểu thức

            A =cos ² 330  +cos ² 570  -2.+cos150 - sin 750

   b) Cho sinx = không tính góc nhọn x hãy tính cosx ,tanx  ,cotx

Bài 3 :(2 Điểm ) Cho  vuông tại A có AB = 18cm, AC = 24cm..Giải tam giác ABC

Bài 4 :(3 Điểm ) Cho  vuông tại A ( AB < AC ) Đường cao AH ,phân giác AD.

      a)Chứng minh :

          b)Veõ,tia BI cắt AC tại M .Chứng minh :

          c)Chứng minh :

 

 

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