Решение №16070: \(\left ( \left ( \frac{1}{a}+\frac{1}{b+c} \right ):\left ( \frac{1}{a}-\frac{1}{b+c} \right ) \right ):\left ( 1+\frac{b^{2}+c^{2}-a^{2}}{2bc} \right )=\left ( \frac{a+b+c}{a\left ( b+c \right )}:\frac{-a+b+c}{a\left ( b+c \right )} \right ):\frac{2bc+b^{2}+c^{2}-a^{2}}{2bc}=\frac{a+b+c}{-a+b+c}\cdot \frac{2bc}{\left ( b+c \right )^{2}-a^{2}}=\frac{2\left ( a+b+c \right )bc}{\left ( -a+b+c \right )\left ( b+c-a \right )\left ( b+c+a \right )}=\frac{2bc}{\left ( -a+b+c \right )^{2}}=\frac{2\cdot 0.625\cdot 3.2}{\left ( -1\frac{33}{40}+0.625+3.2 \right )^{2}}=\frac{4}{\left ( -1.825+3.825 \right )^{2}}=\frac{4}{4}=1\)

Ответ: 1

Решение №16073: \(\left ( x^{2}+2x-\frac{11x-2}{3x+1} \right ):\left ( x+1-\frac{2x^{2}+x+2}{3x+1} \right )=\frac{3x^{3}+6x^{2}+x^{2}+2x-11x+2}{3x+1}:\frac{3x^{2}+3x+x+1-2x^{2}-x-2}{3x+1}=\frac{3x^{3}+7x^{2}-9x+2}{3x+1}\cdot \frac{3x+1}{x^{2}+3x-1}=\frac{3x^{3}+7x^{2}-9x+2}{x^{2}+3x-1}=\frac{3x^{3}+9x^{2}-3x-2x^{2}-6x+2}{x^{2}+3x-1}=\frac{3x\left ( x^{2}+3x-1 \right )-2\left ( x^{2}+3x-1 \right )}{x^{2}+3x-1}=\frac{\left ( x^{2}+3x-1 \right )\left ( 3x-2 \right )}{x^{2}+3x-1}=3x-2=3\cdot 7.(3)-2=3\cdot 7\frac{3}{9}-2=22-2=20\)

Ответ: 20

Решение №16077: \(\frac{\left ( \frac{1}{a}+\frac{1}{b}-\frac{2c}{ab} \right )\left ( a+b+2c \right )}{\frac{1}{a^{2}}+\frac{1}{b^{2}}+\frac{2}{ab}-\frac{4c^{2}}{a^{2}b^{2}}}=\frac{\frac{a+b-2c}{ab}\left ( a+b+2c \right )}{\frac{a^{2}+2ab+b^{2}-4c^{2}}{a^{2}b^{2}}}=\frac{\left ( a+b-2c \right )\left ( a+b+2c \right )a^{2}b^{2}}{\left ( \left ( a+b \right )^{2}-\left ( 2c \right )^{2} \right )ab}=\frac{\left ( a+b-2c \right )\left ( a+b+2c \right )ab}{\left ( a+b-2c \right )\left ( a+b+2c \right )}=ab=7.4\cdot \frac{5}{37}=\frac{37}{5}\cdot \frac{5}{37}=1\)

Ответ: 1

Решение №16078: \(\left ( \frac{1}{t^{2}+3t+2}+\frac{2t}{t^{2}+4t+3}+\frac{1}{t^{2}+5t+6} \right )^{2}\cdot \frac{\left ( t-3 \right )^{2}+12t}{2}=\left ( \frac{t+3+2t\left ( t+2 \right )+t+1}{\left ( t+1 \right )\left ( t+2 \right )\left ( t+3 \right )} \right )^{2}\cdot \frac{t^{2}+6t+9}{2}=\frac{\left ( 2\left ( t+2 \right )\left ( t+1 \right ) \right )^{2}\left ( t+3 \right )^{2}}{2\left ( \left ( t+1 \right )\left ( t+2 \right )\left ( t+3 \right ) \right )^{2}}=2\)

Ответ: 2

Решение №16080: \(\left ( \frac{2-b}{b-1} +2\frac{a-1}{a-2}\right ):\left ( b\frac{a-1}{b-1}+a\frac{2-b}{a-2} \right )=\frac{ab-2}{\left ( b-1 \right )\left ( a-2 \right )}\cdot \frac{\left ( b-1 \right )\left ( a-2 \right )}{a^{2}b-ab^{2}-2a+2b}=\frac{ab-2}{ab\left ( a-b \right )-2\left ( a-b \right )}=\frac{ab-2}{ab\left ( a-b \right )-2\left ( a-b \right )}=\frac{ab-2}{\left ( a-b \right )\left ( ab-2 \right )}=\frac{1}{a-b}=\frac{1}{\sqrt{2}+0.8-\sqrt{2}+0.2}=1\)

Ответ: 1