Question

Розв'яжіть функції!!!! 10балів

Answer 1

1)

$sqrt{x + 2} - x = 0 \ sqrt{x + 2} = x \ x + 2 = x {}^{2} \ - x {}^{2} + x + 2 = 0 \ d = 1 - 4 times ( - 1) times 2 = 9 \ x1 = 2 \ x2 = - 1$

2)

$x {}^{3} - 3x {}^{2} + x - 3 = 0 \ x {}^{2} (x - 3) - (x - 3) = 0 \ - (x - 3) times (x {}^{2} + 1) = 0 \ - (x - 3) = 0 \ x = 3 \ x { }^{2} + 1 = 0 \ x {}^{2} = -1$

3)

$- |x - 2| = - 1 \ |x - 2| = 1 \ x - 2 = 1 \ x - 2 = - 1 \ x = 3 \ x = 1$

4)

$frac{x {}^{2} - 2x - 15}{x + 3} \ frac{x(x + 3) - 5(x + 3)}{x + 3} \ frac{(x + 3)(x - 5)}{x + 3} \ x - 5 = 0 \ x = 5$