1) {z + 3 > 3z - 1 {5z - 1 > 6 - 2z {z - 3 < 0 2) {0.7 (1 + 5z) < 0.5 (z + 1) + 3z {2z -...

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1) {z + 3 > 3z - 1
{5z - 1 > 6 - 2z
{z - 3 < 0

2) {0.7 (1 + 5z) < 0.5 (z + 1) + 3z
{2z - (2 - 1.7) > 6.7


Алгебра (155 баллов) | 76 просмотров
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{z+3>3z-1⇒3z-z<3+1⇒2z<4⇒z<2<br>{5z-1>6-2z⇒5z+2z>6+1⇒7z>7⇒z>1
{z-3<0⇒z<3<br>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
                  ////////////////////////////////////////////////////
--------------(1)-------------(2)------------(3)-------
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
x∈(1;2)

{0,7(1+5z)<0,5(z+1)+3z⇒0,7+3,5z<0,5z+0,5+3z⇒3,5z-3,5z<-0,7 нет решен<br>{2z-(2-1,7)>6,7⇒2z-0,3>6,7⇒2z>7⇒z>3,5
x∈∅

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