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\(M=\frac{-2x}{3}+3x\left(\frac{x}{6}-\frac{-2}{9}-\frac{7}{5}\right)-\frac{5x}{2}\left(\frac{x}{5}-\frac{4}{5}\right)\)
\(M=\frac{-2x}{3}+3x\left(\frac{x}{6}+\frac{2}{9}-\frac{7}{5}\right)-\frac{5x}{2}.\frac{x-4}{5}\)
\(M=\frac{-2x}{3}+3x\left(\frac{15x+20-126}{90}\right)-\frac{5x^2-20x}{10}\)
\(M=\frac{-2x}{3}+3x.\frac{15x-106}{90}-\frac{5.\left(x^2-4x\right)}{10}\)
\(M=\frac{-2x}{3}+\frac{45x^2-318x}{90}-\frac{x^2-4x}{2}\)
a) \(x\ge\frac{2}{3}\Rightarrow3x-2\ge0\Rightarrow\left|3x-2\right|=3x-2\)
\(\Rightarrow P=\frac{1}{2}-\frac{1}{2}\left(x:\frac{1}{6}-\frac{1}{4}\right)-2\left(3x-2\right)\)
\(\Rightarrow P=\frac{1}{2}-\frac{1}{2}\left(6x-\frac{1}{4}\right)-6x+4\)
\(\Rightarrow P=\frac{4}{8}-3x+\frac{1}{8}-6x+\frac{32}{8}\)
\(\Rightarrow P=\frac{37}{8}-9x\)
b) \(x< \frac{2}{3}\Rightarrow3x-2< 0\Rightarrow\left|3x-2\right|=2-3x\)
\(\Rightarrow P=\frac{1}{2}-\frac{1}{2}\left(x:\frac{1}{6}-\frac{1}{4}\right)-2\left(2-3x\right)\)
\(\Rightarrow P=\frac{1}{2}-\frac{1}{2}\left(6x-\frac{1}{4}\right)-4+6x\)
\(\Rightarrow P=\frac{4}{8}-3x+\frac{1}{8}-\frac{32}{8}+6x\)
\(\Rightarrow P=\frac{-27}{8}+3x\)
\(P\left(x\right)-Q\left(x\right)=\left(-2x+\frac{1}{2}x^2+3x^4-3x^2-3\right)-\left(3x^4+x^3-4x^2+1,5x^3-3x^4+2x+1\right)\\ P\left(x\right)-Q\left(x\right)=-2x+\frac{1}{2}x^2+3x^4-3x^2-3-3x^4-x^3+4x^2-1,5x^3+3x^4-2x-1\\ P\left(x\right)-Q\left(x\right)=\left(-2x-2x\right)+\left(\frac{1}{2}x^2-3x^2+4x^2\right)+\left(3x^4-3x^4+3x^4\right)+\left(-3-1\right)+\left(-x^3-1,5x^3\right)\\ P\left(x\right)-Q\left(x\right)=-4x+\frac{3}{2}x^2+3x^4-4-\frac{5}{2}x^3\)
\(R\left(x\right)+P\left(x\right)-Q\left(x\right)+x^2=2x^3-\frac{3}{2}x+1\\ \Rightarrow R\left(x\right)+\left(P\left(x\right)-Q\left(x\right)\right)+x^2=2x^3-\frac{3}{2}x+1\\ \Rightarrow R\left(x\right)-4x+\frac{3}{2}x^2+3x^4-4-\frac{5}{2}x^3+x^2=2x^3-\frac{3}{2}x+1\\ \Rightarrow R\left(x\right)-4x+\left(\frac{3}{2}x+x^2\right)+3x^4-4-\frac{5}{2}x^3=2x^3-\frac{3}{2}x+1\\ \Rightarrow R\left(x\right)-4x+\frac{5}{2}x^2+3x^4-4-\frac{5}{2}x^3=2x^3-\frac{3}{2}x+1\\ \Rightarrow R\left(x\right)=2x^3-\frac{3}{2}x+1+4x-\frac{5}{2}x^2-3x^4+4+\frac{5}{2}x^3\\ \Rightarrow R\left(x\right)=\left(2x^3+\frac{5}{2}x^3\right)+\left(\frac{-3}{2}x+4x\right)+\left(1+4\right)-\frac{5}{2}x^2-3x^4\\ \Rightarrow R\left(x\right)=\frac{9}{2}x^3+\frac{5}{2}x+5-\frac{5}{2}x^2-3x^4\)
\(\frac{1}{3}\left(2-3x\right)-\frac{1}{7}\left(4x-2\right)+\frac{1}{2}\left(x-3\right)=1\)
\(\frac{2}{3}-x-\frac{4}{7}x+\frac{2}{7}+\frac{x}{2}-\frac{3}{2}=1\)
\(\left(\frac{2}{3}+\frac{2}{7}-\frac{3}{2}\right)+\left(-1-\frac{4}{7}+\frac{1}{2}\right)x=1\)
\(-\frac{23}{42}-\frac{15}{14}x=1\)
\(\frac{15}{14}x=-\frac{23}{42}-1\)
\(\frac{15}{14}x=-\frac{65}{42}\)
\(x=-\frac{65}{42}:\frac{15}{14}\)
\(x=-\frac{13}{9}\)