外国数学 微积分题目.高手帮忙啊.这题微积分题目.往高手帮忙.答对了加30分!百分百!先不给分,不然怕等等没人懂啊.A construction worker throws a bolt upwards and out while working on the North Dundas Tower 800m a
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外国数学 微积分题目.高手帮忙啊.这题微积分题目.往高手帮忙.答对了加30分!百分百!先不给分,不然怕等等没人懂啊.A construction worker throws a bolt upwards and out while working on the North Dundas Tower 800m a
外国数学 微积分题目.高手帮忙啊.
这题微积分题目.往高手帮忙.答对了加30分!百分百!先不给分,不然怕等等没人懂啊.
A construction worker throws a bolt upwards and out while working on the North Dundas Tower 800m above the ground, After t seconds, the height of the bolt is given by h(t)=-4.9t^2+20t+800. Round to one decimal place if requgired.(Note:You must use Calculus and interpret any negitive results)
a: what is the velocity of the bole at its maximum height?
b: What time does the bolt reach its maximum height and what is the maximum height?
c: Determine the velocity at which the bolt strucks the ground (impact velocity)
d:determine the acceleration of the bolt. What is the significance of this result?
外国数学 微积分题目.高手帮忙啊.这题微积分题目.往高手帮忙.答对了加30分!百分百!先不给分,不然怕等等没人懂啊.A construction worker throws a bolt upwards and out while working on the North Dundas Tower 800m a
a) 0,因为是向上抛,最高的时候速度是0
b)v=dx/dt= -9.8t+20 最高的时候v=0推出 t 约等于2.0,将t代入h(t)得出高度约等于820.4m
c)落在地上h=0,得出t约为14.98029999,代入v=9.8t+20 约等于-126.8m/s 答案就是126.8m/s 方向朝下
d)a=dv/dt=-9.8 这个说明加速度是恒定的（constant）突然想到题目说负的要说明方向.那加速度就是9.8,方向朝下.
给分吧,不懂得可以问我
a. 0
b. v(t)=-9.8t+20
0=-9.8t+20
t=2.0s
h(t)=-4.9(2.0)^2+20(2.0)+800
=820.4m
c. 0=-4.9t^2+20t+800=15 s
v(t)=-9.8(15)+20=-127
d. a(t)=-9.8
我比较可耻，不信LZ会给分……所以不答……
说真的这挺简单的呀，看题目还以为是differential那些呢……