Х=4у-12
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![\frac{x-1+\frac{1}{x}}{1-\frac{1}{x}}\; ,\; \; \; \; ODZ:\; \; x\ne 0\; \; i\; \; 1-\frac{1}{x}\ne 0\; \; \to \; \; x\ne 0\; i\; \; \; \frac{x-1}{x}\ne 0\; ,\\\\x\ne 0\; \; i\; \; x\ne 1\; \; \Rightarrow \; \; x\in (-\infty ,0)\cup (0,1)\cup (1,+\infty )\\\\x=-1:\; \; \frac{x-1+\frac{1}{x}}{1-\frac{1}{x}}=\frac{x^2-x+1}{x-1}=\frac{-1-1-1}{1+1}=-\frac{3}{2}=-1,5\\\\x=\frac{1}{2}:\; \; \frac{x^2-x+1}{x-1}=\frac{\frac{1}{4}-\frac{1}{2}+1}{\frac{1}{2}-1}=\frac{\frac{3}{4}}{-\frac{1}{2}}=-\frac{3\cdot 2}{4\cdot 1}=-\frac{3}{2}=-1,5](https://tex.z-dn.net/?f=%5Cfrac%7Bx-1%2B%5Cfrac%7B1%7D%7Bx%7D%7D%7B1-%5Cfrac%7B1%7D%7Bx%7D%7D%5C%3B+%2C%5C%3B+%5C%3B+%5C%3B+%5C%3B+ODZ%3A%5C%3B+%5C%3B+x%5Cne+0%5C%3B+%5C%3B+i%5C%3B+%5C%3B+1-%5Cfrac%7B1%7D%7Bx%7D%5Cne+0%5C%3B+%5C%3B+%5Cto+%5C%3B+%5C%3B+x%5Cne+0%5C%3B+i%5C%3B+%5C%3B+%5C%3B+%5Cfrac%7Bx-1%7D%7Bx%7D%5Cne+0%5C%3B+%2C%5C%5C%5C%5Cx%5Cne+0%5C%3B+%5C%3B+i%5C%3B+%5C%3B+x%5Cne+1%5C%3B+%5C%3B+%5CRightarrow+%5C%3B+%5C%3B+x%5Cin+%28-%5Cinfty+%2C0%29%5Ccup+%280%2C1%29%5Ccup+%281%2C%2B%5Cinfty+%29%5C%5C%5C%5Cx%3D-1%3A%5C%3B+%5C%3B+%5Cfrac%7Bx-1%2B%5Cfrac%7B1%7D%7Bx%7D%7D%7B1-%5Cfrac%7B1%7D%7Bx%7D%7D%3D%5Cfrac%7Bx%5E2-x%2B1%7D%7Bx-1%7D%3D%5Cfrac%7B-1-1-1%7D%7B1%2B1%7D%3D-%5Cfrac%7B3%7D%7B2%7D%3D-1%2C5%5C%5C%5C%5Cx%3D%5Cfrac%7B1%7D%7B2%7D%3A%5C%3B+%5C%3B+%5Cfrac%7Bx%5E2-x%2B1%7D%7Bx-1%7D%3D%5Cfrac%7B%5Cfrac%7B1%7D%7B4%7D-%5Cfrac%7B1%7D%7B2%7D%2B1%7D%7B%5Cfrac%7B1%7D%7B2%7D-1%7D%3D%5Cfrac%7B%5Cfrac%7B3%7D%7B4%7D%7D%7B-%5Cfrac%7B1%7D%7B2%7D%7D%3D-%5Cfrac%7B3%5Ccdot+2%7D%7B4%5Ccdot+1%7D%3D-%5Cfrac%7B3%7D%7B2%7D%3D-1%2C5)
При х=0 и х=1 выражение не имеет смысл, при х=-1 и х=1/2 выражение принимает значение (-1,5) .
(x^2 -y^2)/xy / (x^2+y^2-2xy/xy)
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А)<span><span>(<span><span>x2</span>+x</span>)</span><span>(<span>49−<span>x2</span></span>)</span>=</span>Раскрытие скобок:<span><span>x2</span>49+<span>x4</span><span>(<span>−1</span>)</span>+x49+<span>x3</span><span>(<span>−1</span>)</span>=</span><span>49<span>x2</span>−<span>x4</span>+49x−<span>x3</span>=</span><span>−<span>x4</span>−<span>x3</span>+49<span>x2</span>+49x</span>Ответ: <span>−<span>x4</span>−<span>x3</span>+49<span>x2</span>+49x
В)</span><span><span>(<span><span>x2</span>−7</span>)</span><span>(<span><span>x2</span>+18</span>)</span>=</span>Раскрытие скобок:<span><span>x4</span>+<span>x2</span>18−7<span>x2</span>−126=</span><span><span>x4</span>+11<span>x2</span>−126</span>Ответ: <span><span>x4</span>+11<span>x2</span>−126
Д)</span><span><span>(<span><span>x2</span>−3<span>x2</span></span>)</span><span>(<span><span>x2</span>+7</span>)</span>=</span>Приведение подобных:<span><span>(<span>−2<span>x2</span></span>)</span><span>(<span><span>x2</span>+7</span>)</span>=</span>Раскрытие скобок:<span>−2<span>x4</span>−14<span>x2</span></span>Ответ: <span><span>−2<span>x4</span>−14<span>x2
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