cac ban giup minh lam bai nay nhe
12^25+25^21-21*(2/5*9)/3 chung minh chia het cho 54
giup minh nhe cam on cac ban nhieu
nho cac ban lam ho minh bai nay:tim gia tri nho nhat:
C=/x + 32/ + /54 - x/
cam on ban nhieu nhe !
Cho tam giac ABC can tai B ke BH vuong goc AC ( H thuoc AC )
a) Chung minh: HA = HC
b) Ke HD vuong goc AB ( D thuoc AB ), HE vuong goc BC ( E thuoc BC ). Chung minh: HD = HE
c) Chung minh: tam giac BDE can
d) Chung minh: \(BE^2+DH^2=BC^2-HA^2\)
MINH DANG CAN GAP NHO CAC BAN GIUP CHO ( phan a, b, c cac ban co the lam hoac ko thi tuy nhung nho cac ban giup minh phan d )
CAM ON CAC BAN NHIEU
Cho tam giac ABC can tai A. Phan giac AM \(\left(M\in BC\right)\), co AB = 5cm, BC = 6cm
a) Chung minh: tam giac AMB = tam giac AMC
b) Chung minh: Am vuong goc BC
c) Tinh AM
d) Qua B ve duong thang a vuong goc voi AC va cat AM tai H. Chung minh: CH vuong goc AB
MINH DANG CAN RAT RAT GAP NHO CAC BAN GIAI GIUM CHO MINH ( cac ban muon giai phan a, b, c ko thi tuy nhung nho cac ban giup minh phan d voi )
CAM ON CAC BAN NHIEU
bai 5 cho A= 36*45*720
hai A co tat a bao nhieu uockhong ci
hia het cho 25
cac ban neu cach lam cho minh nha xin cam on
cac ban giup minh lam bai toan nay voi! Cam On cac ban nhieu!
cho tam giac ABC can tai dinh A . Tren canh AB lay diem D, tren tia doi cua tia CA lay diem E sao cho BD = CE.
Goi I la trung diem cua DE . Chung minh 3 diem B, I, C thang hang
chung minh rang ton tai so tu nhien gom toan cac chu so 1 va 0 chia het cho 23
1.chung to
a)(n+2016^2017).n+2017^2016 chia het cho 2
b)(n-5(n)) chia het cho 9 voi S (n) la tong cac chu so cua n
c)5^10-5^8 chia het cho 12
d)3^28-3^27-3^26 chia het cho 45
chung minh rang\(16^5-2^{15}\)chia het cho 31