Допоможіть будь-ласка

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Допоможіть будь-ласка


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Алгебра (19 баллов) | 41 просмотров
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( \frac{5x}{x-10}+ \frac{20x}{x^2-20x+10} ): \frac{4x-24}{x^2-100} - \frac{25x}{x-10}= \frac{5x}{4}

Решение:
5x( \frac{1}{x-10}+ \frac{4}{x^2-20x+10} )* \frac{x^2-100}{4(x-6)} - \frac{25x}{x-10}= \frac{5x}{4}

5x* \frac{x^2-20x+10+4(x-10)}{(x-10)(x^2-20x+10)}* \frac{(x-10)(x+10)}{4(x-6)} - \frac{25x}{x-10}= \frac{5x}{4}

5x* \frac{x^2-16x-30}{x^2-20x+10}* \frac{x+10}{4(x-6)} - \frac{25x}{x-10}= \frac{5x}{4}

Умножим обе части уравнения на 4/5
x* \frac{x^2-16x-30}{x^2-20x+10}* \frac{x+10}{(x-6)} - \frac{20x}{x-10}= x

x* \frac{x^2-16x-30}{x^2-20x+10}* \frac{x+10}{(x-6)} - \frac{20x}{x-10}- x =0

x(\frac{x^2-16x-30}{x^2-20x+10}* \frac{x+10}{(x-6)} - 1 -\frac{20}{x-10}) =0

x(\frac{(x^2-16x-30)(x+10)-(x^2-20x+10)(x-6)}{(x^2-20x+10)(x-6)} -\frac{20}{x-10}) =0

x(\frac{x^3-6x^2-190x-300-(x^3-26x^2+130x-60)}{(x^2-20x+10)(x-6)} -\frac{20}{x-10}) =0

x(\frac{20x^2-320x-240}{(x^2-20x+10)(x-6)} -\frac{20}{x-10}) =0

x(\frac{x^2-16x-12}{(x^2-20x+10)(x-6)} -\frac{1}{x-10}) =0

x*\frac{(x^2-16x-12)(x-10)-(x^2-20x+10)(x-6)}{(x^2-20x+10)(x-6)(x-10)} =0

x*\frac{x^3-26x^2+148x+120-(x^3-26x^2-130x-60)}{(x^2-20x+10)(x-6)(x-10)} =0

x*\frac{18x+180}{(x^2-20x+10)(x-6)(x-10)} =0

x*\frac{18(x+10)}{(x^2-20x+10)(x-6)(x-10)} =0

\frac{x(x+10)}{(x^2-20x+10)(x-6)(x-10)} =0

x=0,    x=-10

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