rains

\(\left\{{}\begin{matrix}16-x^2\ge0\\2x+1>0\\x^2-8x+14\ge0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}-4\le x\le4\\x>-\dfrac{1}{2}\\\left[{}\begin{matrix}x\ge4+\sqrt{2}\\x\le4-\sqrt{2}\end{matrix}\right.\end{matrix}\right.\Leftrightarrow-\dfrac{1}{2}< x\le4-\sqrt{2}\)

`650650/480480 = (65xx 10010)/(48 xx 10010) = 65/48`

`222222/144144=(37 xx 6006)/(24 xx 6006) = 37/24 = 74/48`

Vì `65/48 < 74/48 => 650650/480480 <222222/144144`

`(x+5)/(x+1)<1`

`(x+1+4)/(x+1)<1`

`1+4/(x+1)<1`

`4/(x+1)<0`

`x+1<0`

`x<-1`

`cos α+sinα=5/4`

`<=>(cosα+sinα)^2=25/16`

`<=>(sin^2α+cos^2α)+2sinαcosα=25/16`

`<=>1+2sinαcosα=25/16`

`<=>sinα.cosα=9/32`

`S=3x^2+2x+1`

`=(3x^2+2x+1/3)+2/3`

`=[(\sqrt3 x)^2+ 2.\sqrt3 x . 1/\sqrt3 + (1/\sqrt3)^2]+2/3`

`=(\sqrt3 x+1/\sqrt3)^2 + 2/3`

`=(\sqrt3x+\sqrt3/3)^2+2/3`

`=> D_(min) =2/3 <=> \sqrt3x+\sqrt3/3=0 <=>x=-1/3`

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