Verified answer

7) A=0.5 м

ω=π/3

T=2*π/ω=6 c

v=1/T≈0.17 Гц

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8) A=0.1 м

T=4 c

v=1/T=0.25 Гц

ω=2*π/T=π/2

x=0.1*sin(π/2)*t

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