Номер 896(1,2);номер 878;номер 904(1)

Question

Математика

Kenn

7 год назад

Номер 896(1,2);номер 878;номер 904(1)

ОТВЕТЫ

Памфил

Jul 4, 2019

896.1
$\frac{7(x-6)}{4} = \frac{5(x+1)}{3} -3(x+2) \\ \frac{3(7x-42)}{12} = \frac{4(5x+5)}{12}- \frac{12(3x+6)}{12} \\ \frac{21x-126}{12} = \frac{20x+20-36x-72}{12} \\ \frac{21x+16x-126+52}{12} =0 \\ 37x-74=0 \\ 37x=74 \\ x=2 \\ OTBET:2$
896.2
$\frac{3(x-8)}{5}+ \frac{7(x+5)}{6} = \frac{4(7x+1.5)}{15} + \frac{1}{3} \\ \frac{6(3x-24)}{30} + \frac{5(7x+35)}{30} = \frac{2(28x+6)}{30} + \frac{10}{30} \\ \frac{18x-144+35x+175}{30} = \frac{56x+12+10}{30} \\ \frac{53x+31-56x-22}{30} \\ -3x+9=0 \\ 3x=9 \\ x=3 \\ OTBET:3$
904.1
$\frac{2}{2+ \frac{1}{2+ \frac{1}{2+x} } } =1 \\ \frac{2}{2+ \frac{1}{\frac{4+2x+1}{2+x} } } = 1 \\ \frac{2}{2+ \frac{1}{\frac{5+2x}{2+x} } } = 1 \\ \frac{2}{2+ \frac{2+x}{5+2x} } } = 1 \\ \frac{2}{ \frac{10+4x+2+x}{5+2x} } } = 1 \\ \frac{2}{\frac{12+5x}{5+2x} } } = 1 \\ \frac{2(5+2x)}{12+5x} =1 \\ \frac{10+4x}{12+5x} =1 \\ \frac{10+4x-12-5x}{12+5x}=0 \\ \frac{-2-x}{12+5x} =0 \\ \left \{ {{-2-x=0} \atop {2+x \neq 0}} \right. \\ \left \{ {{x=-2} \atop {x \neq -2}} \right.$
Ответ: нет решений.

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