Решить уравнениеа) tgx=-√3 б) 2sin²x+sinx-1

Question

Решить уравнение
а) tgx=-√3
б) 2sin²x+sinx-1

Answer 1

X=arctg a+πn
x=arctg√3+πn
x=π/3+πn

2 sin2x – sinx = 0

sinx (2 sinx – 1) = 0

sinx = 0                                  2sinx – 1 = 0

x 1 = π/2 + πk, k Є R                sinx = ½

                                                x 2 = π/6 + 2 πk,  k Є R

                                                x 3 = 5π/6 + 2 πk,  k Є R