<span>3ctg60(sin310cos70-sin70cos310) =</span>
(aˉ⁴)⁸= а⁻³²
(a³)ˉ⁷ ∙ (aˉ⁴)ˉ⁵ ː (aˉ⁵)⁸= а⁻²¹ * а²⁰ : а⁻⁴⁰ = а⁻¹ : а⁻⁴⁰ = а³⁹
(a⁵bˉ³c⁴)ˉ¹⁰= а⁻⁵⁰ * b³⁰ * с⁻⁴⁰
(a²bˉ³)ˉ³ ∙ (aˉ⁴bˉ⁹)⁶= а⁻⁶ * b⁹ * a⁻²⁴ * b⁻⁵⁴ = a⁻³⁰ * b⁻⁴⁵
3xˇ2-2x-1=0
D=(-2)ˇ2-4.3.(-1)=4+12=16, VD =V(16)=4
x1=1/6(2+4)=1/6.6=1
x2=1/6(2-4)=1/6(-2)=-1/3
x1+x2=1+(-1/3)=2/3
x1.x2=1.(-1/3)=-1/3
(х-10)/х-15 = 2
х-10 = 2(х-15)
х-10 = 2х-30
х-2х = -30+10
-х = -20
х = 20