Найдите сумму целых решений неравенства

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Найдите сумму целых решений неравенства


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Алгебра (14 баллов) | 22 просмотров
Дан 1 ответ
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\frac{-x^2+10x-9+1-2\sqrt{-x^2+10x-9}}{\sqrt{-x^2+10x-9}} \geq 0\\\\
t=\sqrt{-x^2+10x-9}\ \textgreater \ 0\\\\
\frac{t^2+1-2t}{t} \geq 0\\\\
\frac{(t-1)^2}{t} \geq 0\\\\
\frac{(t-1)^2}{t} =0\ \ or\ \ \frac{(t-1)^2}{t} \ \textgreater \ 0\\\\
 \left \{ {{(t-1)^2=0} \atop {t\neq0}} \right. \ \ or\ \ \frac{1}{t}\ \textgreater \ 0\\\\
 \left \{ {{t=1} \atop {t\neq0}} \right. \ \ or\ \ t\ \textgreater \ 0\\\\
t=1\ \ or\ \ t\ \textgreater \ 0\\\\
t\ \textgreater \ 0\\\\
\sqrt{-x^2+10x-9}\ \textgreater \ 0\\\\

\left \{ {{0 \geq 0} \atop {-x^2+10x-9\ \textgreater \ 0^2}} \right. \ \ or\ \ \left \{ {{0\ \textless \ 0} \atop {-x^2+10x-9 \geq 0}} \right. \\\\
-x^2+10x-9\ \textgreater \ 0\\\\
x^2-10x+9\ \textless \ 0\\\\
x^2-x-9x+9\ \textless \ 0\\\\
x(x-1)-9(x-1)\ \textless \ 0\\\\
(x-1)(x-9)\ \textless \ 0\\\\
x\in(1;\ 9)

Целые сумма целых решений: 2+3+4+5+6+7+8=35

Ответ: 35

\sqrt{T}\ \textgreater \ U\ \ \ \textless \ -\ \textgreater \ \\\\
\ \textless \ -\ \textgreater \ \ \ \left \{ {{T \geq 0} \atop {T\ \textgreater \ U^2}} \right. \ or\ \left \{ {{U\ \textless \ 0} \atop {T \geq 0}} \right.
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