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thanhdangdung


[FONT=.VnTime]1.Mot vat dao dong dieu hoa voi phuong trinh X=acos(4nt+n/6)cm.Thoi diem thu 2009 va qua vi tri x=2cm.[/FONT]
[FONT=.VnTime]A:12049/24[/FONT]
[FONT=.VnTime]B:12061/24[/FONT]
[FONT=.VnTime]C:12025/24[/FONT]
[FONT=.VnTime]D:dap an khac[/FONT]
[FONT=.VnTime]2.phuong trinh li do cua con lac lo xo X=3cosnt(cm,s)[/FONT]
[FONT=.VnTime]_thoi gian de qua cau dao dong tu vi tri can bang den vi tri X1=1.5cm la:[/FONT]
[FONT=.VnTime]A:0.6s B:0.4s c:1/3cm D:0.25s[/FONT]
[FONT=.VnTime]
[FONT=.VnTime]A:12049/24[/FONT]
[FONT=.VnTime]B:12061/24[/FONT]
[FONT=.VnTime]C:12025/24[/FONT]
[FONT=.VnTime]D:dap an khac[/FONT]
[FONT=.VnTime]2.phuong trinh li do cua con lac lo xo X=3cosnt(cm,s)[/FONT]
[FONT=.VnTime]_thoi gian de qua cau dao dong tu vi tri can bang den vi tri X1=1.5cm la:[/FONT]
[FONT=.VnTime]A:0.6s B:0.4s c:1/3cm D:0.25s[/FONT]
[FONT=.VnTime]