2. 2sin (5x+π/3)=√2
sin (5x+π/3)=√2/2
5x+π/3=π/4+2πk, k целое 5x+π/3=3π/4+2πk, k целое
5x=-π/12+2πk, k целое 5x=5π/12+2πk, k целое
x=-π/60+2πk/5, k целое x=π/12+2πk/5, k целое
5. cos (2x-π/3)<1/2<br>π/3+2πk <2x-π/3<5π/3+2πk, k целое<br>2π/3+2πk <2x <2π+2πk, k целое<br>π/3+πk