hay chung minh rang a- b va b-a la 2 so doi nhau
Ai nhanh tick c ho
Cho a,b,c thuoc Z,biet ab-ac+bc-c^2=1.Chung minh a va b la 2 so doi nhau
1)CMR:(a+b-c)+(a-b)-(a-b-c)=a+b
2)chung minh A va B la hai so doi nhau biet:A=a-b+c;B=-a+b-c
3)cho a-b=1.tinhS biet :
S=-(a-b-c)+(-c+b+a)-(a+b)
ai lam duov 5 tick luon
cho doan thang AB va trung diem M cua no a. chung minh rang neu C la diem thuoc tia doi cua tia BA thi CM= (CA +CB)/2 b. chung to rang neu C la diem nam giua M va B thi CM =( CA -CB )/2
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.
~~~~~~~~~~~~~Giup tui voi!!!!!~~~~~~~~~~~~~~
cho a va b la hai so nguyen to cung nhau chung minh rang a^2+b^2/a.b la phan so toi gian
Cho n so nguyen bat ki a;b;c;...;n
Chung Minh Rang : (a+b)+(b+c)+...+(z+n) la 1 so chan
cho a b c thuộc z
biet ab-ac+bc-c^2=-1
chung minh a va b hai so doi nau
cho a+ b = p la snt . chung to rang a va b la hai so nguyen to cung nhau . minh can gap