3.28 y= - x² и y-x =- 2 ==> y= - x² и y = x - 2
- x² = x -2
x² +x -2 =0
x₁= -2 ==>y₁= - 4
x₂ = 1 ==> y₂=-1
ответ : { (-2 ; -4) ; (1;-1) }
4.28 интеграл (d(x+1)/(1+(x+1)²) = arctq(x+1) x--> -∞ и x-->∞
arctq(-∞) = - π/2
arctq(∞) = π/2
π/2 - (- π/2 ) = π