(а+3)*(9а-8)-(2+а)*(9а-1)= 9a2-8а+27а-24-(18а-2+9a2-а)=9a2-8а+27а-24-18а+2-9а2+а=а-22+а=2а-22=2*(а-11)
Sin 3x - Sin 7x = √<span>3 Sin 2x
-2Cos5x Sin2x = </span>√3Sin2x
-2Cos5x Sin2x - √3Sin2x = 0
2Cos5x Sin2x + √3Sin2x = 0
Sin2x(2Cos5x + √3) = 0
Sin2x = 0 2Cos5x +√3 = 0
2x = πn , n∈Z Cos5x = -√3/2
x = nπ/2, n ∈ Z 5x = +-arcCos(√3/2) + 2πk , k ∈Z
5x = +-π/6 + 2πk , k ∈Z
x = +-π/30 + 2πk/2, k ∈Z
Ответ:5
Объяснение:m^6=(m^3)^2, след. 6^2-31=36-31=5