Предмет: Алгебра, автор: nkenig

х2-3х+корень из 5-х=корень из 5-х+18

Ответы

Автор ответа: Аноним

ОДЗ: $5-x geq 0$ откуда $x leq 5$ (подкоренное выражение принимает неотрицательные значения)

$x^2-3x+ sqrt{5-x}- sqrt{5-x} -18=0\ \x^2-3x-18=0$

Согласно теореме Виета: $x_1=-3$ и $x_2=6$ . Корень $x_2notin (-infty;5]$

Ответ: $-3.$

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No one knew how Mr. Sticky got in the fish tank.

"He's very small," Mum said as she peered at the tiny water snail. "Just a black dot."

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