1.Tim cac so tu nhien x sao cho:
a/6 chia het cho (x-1) b/14 chia het cho (2.x+3)
2.Ve hinh de thay rang moi cau sau day la sai
a/Hai tia chung goc luon la hai tia doi nhau
b/Hai tia chung goc luon la hai tia trung nhau
c/Hai tia chung hoc luon la hai tia phan biet
d/Hai tia co nhieu diem chung chi khi chung la hai tia trung nhau
e/Hai tia phan biet va co chung goc luon la hai tia doi nhau
f/Hai tia ko chung goc luon la hai tia khong co diem chung
3/
a/Ve 3 diem thang hang A,B,C sao cho diem B nam giua hai diem A,C.Sau do hay ke ten:cac tia,cac cap tia doi nhau,cac cap tia phan biet,cac cap tia trung nhau co trong hinh ve do.
b/Ve 4 diem A,B,C,D tren mot duong thang sao cho diem B nam giua hai diem A,C va diem C nam giua hai diem B,D.Sau do hay ke ten:cac tia,cac cap tia doi nhau,cac cap tia phan biet,cac cap tia trung nhau co trong hinh ve do.
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