Відповіді АЛГЕБРА: 21.14

21.14

1) g(x) = x + 2cosx;

g’(x) = 1 – 2 sinx = 0;

1 – 2sinx = 0;

sinx = –12

x = (–1)ⁿ⁺¹ π6 + πn, n є z.

2) f(x) = 3+ x2x+1

f‘(x) = 2xx+1- (3+ x2)(x+1)2 = 2x2+ 2x-3- x2(x+1)2 = x2+ 2x-3(x+1)2 = 0;

x² + 2x – 3 = 0;

x₁ = –3; x₂ = 1.