B(в 2) - 36 - 3b(в 2)-6b= -36-2b(в 2)-6b
Решение
<span>(x+6)(x-9)<0
</span>x + 6 = 0; x₁ = - 6
x - 9 = 0; x₂ = 9
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- 6 9 x
x ∈ (- 6; 9)
ОДЗ: x>=-0,5 и х<=3
Возводим в квадрат обе части.
2x+1>3-x
3x>2
X>2/3
X=(2/3;3]
Sin(6π-π/2)=sin(-π/2)=-1
cos(-13π/4)=cos(13π/4)=cos(3π+π/4)=cos(π+π/4)=-cosπ/4=-√2/2
sin(2π+π/3)=sinπ/3=√3/2
<span>cos(-13π/6)=cos(13π/6)=cos(2π+π/6)=cos(π/6)=</span>√3/2