Arcsin (1/2)=π/6 arccos (-1/√2)=3π/4 arcctg(-√3)=2π/3
<span>3 arcsin (1/2) + 4arccos (-1/√2) - arcctg(-√3)=</span>π/2+3π-2π/3=17π/6
(2x-7)(x+1)+3(4x-1)(4x+1)=2 (5x-2)²-53 2x²-7x+2x-7+3(16x²-1)=2(25x²-20x +4)-53 2x²-5x-7+48x²-3=50x²-40x+8-53 -5x- 10=-40x-45 35x=-35 x=-1
*=ищем как вычитаемое= 7m⁴-9m²n + n²- (3m⁴+6m²n)=7m⁴-9m²n + n²-3m⁴-6m²n=4m⁴-15m²n+ n².
Ответ: 4m⁴-15m²n+ n².