Bien doi tuong BDT
\(\frac{x^2}{x-2}\ge8\)
\(\Leftrightarrow x^2\ge8x-16\)
\(\Leftrightarrow x^2-8x+16\ge0\)
\(\Leftrightarrow\left(x-4\right)^2\ge0\left(True\right)\)
Dau '=' xay ra khi \(x=4\)
Bien doi tuong BDT
\(\frac{x^2}{x-2}\ge8\)
\(\Leftrightarrow x^2\ge8x-16\)
\(\Leftrightarrow x^2-8x+16\ge0\)
\(\Leftrightarrow\left(x-4\right)^2\ge0\left(True\right)\)
Dau '=' xay ra khi \(x=4\)
Chung minh bat dang thuc sau: \(\frac{x^2}{y^2}\)+\(\frac{y^2}{x^2}\)+4>=3(\(\frac{x}{y}\)+\(\frac{y}{x}\))
Giup mk voi . mk can gap lam. Neu thich thi ket ban voi mk nhe
bai 1 sbt toan 8 tap 1 trang 23
dung dinh nghia 2 phan thuc bang nhau chung minh cac dang thuc sau
a)x^2\5=7x^3y^4\35xy
b)x^2(x+2)\x(x+2)^2=x\x+2
d)x^3-x^4\10-5x=-x^2-2x\5
chung minh bat dang thuc: 1/22+1/32+1/42+...+1/n2<1 (n>=2; n thuoc N)
Chung minh dang thuc
x^31+x^30+.....+x+1=(1+x)(1+x^2)(1+x^4)...(1+x^16)
Giup minh nha
chung minh bat dang thuc cosi
cho a,b,c thuoc R chung minh rang a2+b2_> 2ab (1) áp dung va chung minh bat dang thuc sau
(a2+1)(b2+1)(c2+1) _> 8abc
Cho a, b, c,d la cac so thuc . Chung minh bat dang thuc sau:
a2 + b2 +c2 +d2 +e2 >= ab +ac + ad +ae
Lam giup minh nhe cac ban minh can gap lam
x^2+y^2=2 chung min dang thuc 2(x+1)(y+1)=(x+y+2)
chung minh bat dang thuc a4-2a3b+2a2b2-2ab3+b4>=0