2.3
نحسب سرعة الجسم في اللحظة t=0.2 s باستخدام دالة السرعة كدالة للزمن المناسبة لوصف حركة الجسم.
لكي تصف الدالة بشكل صحيح سرعة الجسم، يجب استخدام زاوية الطور الابتدائية «math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨20px¨»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»+«/mo»«mi mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#960;«/mi»«/mstyle»«/math».
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