4x+0.8=5x-3.8
4x-5x=-0.8-3.8
-x=-4.6
x=4.6
Ответ: 4.6
√(3*27) -6= <span>√</span>81-6=9-6=3 .
<span>Решите уравнение!
-2 cos t=0
</span> cos t=0
t=π/2 +πn, n∈Z
<span>9x^2+18x+1=0
x^2+2x+0.11=0
D=4-4*1*0.11=3.56
x=(-2+-</span>√3.56)/2 x(1)≈-1.94
x(2)≈-0.055
-1.94²+(-0.055)²≈3.76