1) t=3
x=10*t+0.4*t²
vo=10 v=10+0.8*t=10+0.8*3=12.4 м/с
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2) x1=4-t x2=3+2*t 4-t=3+2*t t=0.33 c
x1=x2=4-0.33=3.67 м
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3) v1=3 t1=10 t2=t1/2=5 c
vcp=(s1+s2)/(t1+t2)
s1=v1*t1=30 м
vcp=(30+30)/(10+5)=60/15=4 м/с
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