Question

Решить уравнения. Номер 121 (1, 2)

Answer 1

a)2(1/2cosx+√3/2sinx)=1
sin(π/6+x)=1/2
π/6+x=(-1)^n *π/6*πn
x=-π/6+(-1)^n *π/6*πn⇒(-1)^n+1 *π/6+πn
b)1/√2cosx-1/√2sinx=sin3x
sin(π/4-x)=sin3x
sin3x-sin(π/4-x)=0
2sin(2x-π/8)cos(x+π/8)=0
sin(2x-π/8)=0
2x-π/8=πn
2x=π/8+πn
x=π/16+πn/2
cos(x+π/8)=0
x+π/8=π/2+πn
x=-π/8+π/2+πn
x=3π/8+πn