Cho hai duong thang xOx' va yOy' cat nhau tai Otren duong thang xOx' lay ba diem A,B,C sao choOA=OB=BCTren duong thang yoy' lay ba diem M,N,P sao cho OM=ON=NP. chung minh MA,NC,PB cung di qua 1 diem.
GIAI GIUP MINh nhe mn☺☺☺☺☺xin cam on
CM BDT: Voi moi a, b,c > 0, Cmr a/b + b/c + c/a >= 3
Cac ban giup minh Cm cau nay nhe! Minh xin cam on!
cho \(\frac{a}{b-c}+\frac{b}{c-a}+\frac{c}{a-b}=o\)0 chung minh \(\frac{a}{\left(b-c\right)^2}+\frac{b}{\left(c-a\right)^2}+\frac{c}{\left(a-b\right)^2}=0\)
GIUP MK NHA! GAP LAM !
CAM ON NHIEU
giai giup mik vs
cho pt: 3(a-2)x+2a(x-1)=4a+3 (1)
a) giai pt (1) vs a= -2
b) tim a de pt (1) co nghiem x=1
xin cam on
cho phuong trinh (an x):(m-1)x +m^2 -1=0(1) a,giai phuong trinh (1) voi m=2 b, tim gia tri cua m sao cho phuong trinh (1) nhan x=3 lam nghiem
mk dang can gap .cam on truoc a
Cho a,b,c,d > 0. CMR:
1 < (a+b)/(a+b+c) + (b+c)/(b+c+d) + (c+d)/(c+d+a) + ( d+a)/((d+a+b) < 3
Minh da lam dc nua y roi ( y 1<...) con nua y con lai ( ...< 3). Cac ban giup minh lam not nua y cuoi nhe! Minh cam on!
P/s: Minh sap phai nop bai roi, mong cac ban giup minh som nhe, khong minh se bi phat mat! Cam on rat nhiu! That ra thi cung co mot cau hoi giong nhu the nay, nhung ma nua y con lai ma minh chua biet lam lai khong giong nen cac ban giup minh chi tiet mot chut nhe!
a) a/b + b/a >_ 2
b) (a+b)(1/a +1/b)>_ 4
c) (a+b+c) (1/a +1/b +1/c)>_9
2. chung minh rang moi a, b la cac so tuy y, ta co :
a) (a-1)(a-3)(a-4)(a-6) +9 >_ 0
b) 4a(a-b)(a+1)(a+b+1) + b2 >_ 0
3. giai phuong trinh | x2 - x + 2| - 3x + 7 = 0
cau 1 giai phuong trinh sau
a) 7 x -14 =0
b) ( 3x +1 ) ( 2x-2) =0
c) ( 3x -1 ) = x-2
cau 2 giai bat phuong trinh va bieu dien truc nghiem tren truc so
a ) 2x+5 < hoac ( = )9
b) 3x +4 <5x-3
c ) 3x-1 tren 4 >2
cau 3 cho tam giac a bc vuong goc tai a , co ab = 12 cm , ac =16 cm . ke duong cao ah ( hthuoc bc )
a) chung minh : tam giac hba thuoc tam giac abc
b) tinh do dai bc,ah
c) he ad,de,df,la phan giac lan luot cua cac goc bac,hdb,adc,c thuoc a b , d thuoc bc, f thuoc ab
chung minh rang : ea phan eb = db phan dc , fc phan fa = 1
ban nao nhanh minh k cho 10 k
cho a+b+c=1 va 1/a+1/b+1/c=0.Chung minh rang : a^2+b^2+c^2=0
