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Given Information
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Adrian can run 3/4 mile in 1 morning.
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Find how long he needs to run 1 mile
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3/4 miles = 1 morning
[ Divide by 3/4 on both side ]
3/4 ÷ 3/4 miles = 1 ÷ 3/4
1 miles = 4/3 morning
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Find how long he needs to take to run 3 miles
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1 miles = 4/3 morning
[ multiply by 3 through ]
3 miles = 4/3 x 3
3 miles = 4 mornings
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Answer : 4 mornings
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I'm assuming that the diagonals intersect at E. Since diagonals of a parallelogram bisect each other, BE=ED.
- 7x-2=x²-10
- x²-7x-8=0
- (x-8)(x+1)=0
- x = -1, 8
As distance must be positive, we reject the negative case, so x=8.
Thus, BE=ED=54.
Since ![[0,4]=[0,1]\cup(1,4]](https://tex.z-dn.net/?f=%5B0%2C4%5D%3D%5B0%2C1%5D%5Ccup%281%2C4%5D)
, we can rewrite the integral as
Now there is no ambiguity about the definition of f(t), because in each integral we are integrating a single part of its piecewise definition:
Both integrals are quite immediate: you only need to use the power rule
to get
![\displaystyle \int_0^11-3t^2\;dt = \left[t-t^3\right]_0^1,\quad \int_1^4 2t\; dt = \left[t^2\right]_1^4](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cint_0%5E11-3t%5E2%5C%3Bdt%20%3D%20%5Cleft%5Bt-t%5E3%5Cright%5D_0%5E1%2C%5Cquad%20%5Cint_1%5E4%202t%5C%3B%20dt%20%3D%20%5Cleft%5Bt%5E2%5Cright%5D_1%5E4)
Now we only need to evaluate the antiderivatives:
![\left[t-t^3\right]_0^1 = 1-1^3=0,\quad \left[t^2\right]_1^4 = 4^2-1^2=15](https://tex.z-dn.net/?f=%5Cleft%5Bt-t%5E3%5Cright%5D_0%5E1%20%3D%201-1%5E3%3D0%2C%5Cquad%20%5Cleft%5Bt%5E2%5Cright%5D_1%5E4%20%3D%204%5E2-1%5E2%3D15)
So, the final answer is 15.
Six dollars is the only answer that seems correct using the graph. Hope this helped.
