Có gì đâu nkok?
\(A=\dfrac{6\left|y+5\right|+14}{2\left|y+5\right|+14}=\dfrac{6\left|y+5\right|+42}{2\left|y+5\right|+14}-\dfrac{28}{2\left|y+5\right|+14}\)
\(A=\dfrac{3\left(2\left|y+5\right|+14\right)}{2\left|y+5\right|+14}-\dfrac{28}{2\left|y+5\right|+14}\)
\(A=3-\dfrac{28}{2\left|y+5\right|+14}\ge3-\dfrac{28}{14}=1\)
Dấu "=" khi x=-5
Tìm GTNN của :
A = \(x^2+2x-4\)
B = \(\left(x-2\right)^2+\left|y-x\right|+3\)
C = \(\dfrac{6}{5}-\dfrac{14}{5\left|6y-8\right|+35}\)
D = \(\dfrac{6\left|y+5\right|+14}{2\left|y+5\right|+14}\)
1) Cho đa thức \(f\left(x\right)=x^{14}-14.x^{13}+14.x^{12}-...+13.x^2-14.x+14\) Tính f(13)
2) Tính : \(\left(\dfrac{3}{4}-81\right)\left(\dfrac{3^2}{5}-81\right)\left(\dfrac{3^3}{6}-81\right)...\left(\dfrac{3^{2000}}{2003}-81\right)\)
Tìm GTNN của X =\(\dfrac{6}{5}-\dfrac{14}{5\left|6y-8\right|+35}\)
Tìm x, y biết :
\(\left(x+y-2\right)^2+7=\dfrac{14}{\left|y-1\right|+\left|y-3\right|}\)
Tìm GTNN của \(A=\dfrac{5}{\left(x+y\right)^2+\left(y+z\right)^4+\left(z+x\right)^6}\)
Tìm x; y ; z biết :
\(\left(\dfrac{-1}{25}\right)^{14}:\left(2x-1\right)^2=\left(\dfrac{1}{5}\right)^{26}\)
Tìm x,y,z biết
\(\dfrac{3.\left|x\right|+5}{3}=\dfrac{3\left|y\right|-1}{5}=\dfrac{3-z}{7}\) và 2|x|+7|y|+3z=-14
Tìm x:
a)\(5\dfrac{4}{7}:\left\{x:1,3+8,4.\dfrac{6}{7}.\left[6-\dfrac{\left(2,3+5:6,25\right).7}{8.0,0125+6,9}\right]\right\}=1\dfrac{1}{14}\)
b)\(\left|3x-2\right|+\left|2x-1\right|=4\)
Tìm x, y biết :
\(\left|y+3\right|+5=\dfrac{10}{\left(2x-6\right)^2+2}\)
