1) a) \(\sqrt{1-6x+9x^2}+\sqrt{9x^2-12x+4}=\sqrt{\left(1-3x\right)^2}+\sqrt{\left(3x-2\right)^2}\)
\(=\left|1-3x\right|+\left|3x-2\right|\ge\left|1-3x+3x-2\right|=1\)
Vậy: GTNN là 1 khi \(\dfrac{1}{3}\le x\le\dfrac{2}{3}\)
b) Tương tự
2) Không rõ
Voi gia tri nao cua x thi can thuc sau co nghia : \(\sqrt{\dfrac{-2}{x+1}}\)
moi nguoi giup minh cau nay voi , minh cam on!!
moi nguoi giup em bai 4 5 6 voi a em cam on mng
a)\(\sqrt{2+\sqrt{2+\sqrt[]{2+\sqrt{2+...}}}}\)
b)\(\sqrt{6+\sqrt{6+\sqrt{6+\sqrt{6+...}}}}\)
MINH CAN GAP A
may ban tra loi nhanh nha minh can gap
\(\sqrt{4x-20}-3\sqrt{\dfrac{x-5}{9}}=2\)
\(6\sqrt{2}\) + \(\sqrt{6-\sqrt{11}}\)\(-\sqrt{6+\sqrt{11}}\)
thu gon
mik can gap gip mik vs
1,thu gon bieu thuc
a A=\(\dfrac{a\sqrt{a}-8+2a-4\sqrt{a}}{a-4}\)
b,B=\(\dfrac{12\sqrt{6}}{\sqrt{7+2\sqrt{6}-\sqrt{7-2\sqrt{6}}}}\)
c, C=\(\dfrac{\sqrt{c^2+2c+1}}{\left|c\right|-1}\)
2,giai cac phuong trinh
a,\(x^2-9\sqrt{x}+14=0\)
b, \(\sqrt{3x^2-18x+28}+\sqrt{4x^2-24x+45}=-5-x^2+6\)
GIUP MINH VOI MINH CAN GAP
giải phương trình
\(\left(\sqrt{2x+3}-\sqrt{x+1}\right)\left(\sqrt{2x^2+5x+3}+1\right)\)=x+2
giai giup em voi em can gap
cho bieu thuc P= (\(\frac{3x+\sqrt{9x}-3}{x+\sqrt{x}-2}+\frac{1}{\sqrt{x}-1}+\frac{1}{\sqrt{x}-3}\) ): \(\frac{1}{x-1}\)
a) Tim dieu kien de P co nghia, rut gon bieu thuc P.
b) Tim cac so tu nhien x de \(\frac{1}{P}\)la so tu nhien
c) Tinh gia tri cua P voi x= 4-\(2\sqrt{3}\)
Giup mk vs mk dang can gap
help!!!!
1) hai oto cung khoi hanh cung luc tren quang duong tu A den B dai 120km . Moi gio o to thu nhat chay nhanh hon o to thu hai la 10km nen den B truoc o to thu 2 la 0,4 km .tinh van toc moi o to
