Уравнениия)

1.2cos(-x)-\sqrt{2}=0

2.sin(x/3+П/4)=-1

1. 2cos(-x) - √2 = 0

2cosx = √2

cosx = 0,5√2

х = ±π/4 + 2πn     n∈Z

2. sin(x/3+П/4)=-1

x/3+π/4 = -π/2 +2πn

x/3 = -π/2 +2πn - π/4

x/3 = -3π/4 +2πn

x = -9π/4 +6πn    n∈Z

1) 2cos(-x)=√2;

cosx=√2/2;

x=±π/4+2πn. n∈Z.

2) sin(x/3+π/4)=-1;

x/3+π/4=y;

siny=-1;

y=-π/2+2πn. n∈Z.

x/3=-π/2-π/4+2πn. n∈Z.

x/3=-3π/4+2πn. n∈Z.

x=-9π/4+6πn. n∈Z.

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