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X-8 >
√(2x+1)

1 Answer

2 votes


Solution, x-8>√(2x+1)\quad :\quad \begin{bmatrix}\mathrm{Solution:}\:&\:x>3\left(3+√(2)\right)\:\\ \:\mathrm{Decimal:}&\:x>13.24264\dots \\ \:\mathrm{Interval\:Notation:}&\:\left(3\left(3+√(2)\right),\:\infty \:\right)\end{bmatrix}

Steps:


\mathrm{Switch\:sides},√(2x+1)<x-8


\mathrm{Find\:the\:real\:region\:for\:}√(2x+1):\quad x\ge \:-(1)/(2)


\mathrm{Find\:the\:values\:for\:}x-8>0:\quad x>8


\mathrm{Simplify\:and\:compute\:}√(2x+1)<x-8:\quad x<3\left(3-√(2)\right)\quad \mathrm{or}\quad \:x>3\left(3+√(2)\right)


\mathrm{Combine\:the\:following\:ranges:}
x\ge \:-(1)/(2)\quad \mathrm{and}\quad \:x>8\quad \mathrm{and}\quad \left(x<3\left(3-√(2)\right)\quad \mathrm{or}\quad \:x>3\left(3+√(2)\right)\right)

The correct answer is
x>3\left(3+√(2)\right)

Hope this helps!!!

User Jsaporta
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