How do I do number 3??

Mathematics

1 answer:

Alenkinab [10]3 years ago

6 0

Given
d(t)=-16t^2-4t+382

1. times at which rock is 310 from ground
solve d(t)=310=-16t^2-4t+382
=>
16t^2+4t-72=0
t=(-4+/-sqrt(4^2+4*16*72)/(2*16)
=> t=-9/4 or t=2
Reject negative root from context, so
time=2 seconds.

2.
maximum is when d'(t)=0, or
-32t-4=0 => t=-1/8
Therefore rock was descending since t=0 (can also see from -4t, i.e. initial velocity is -4 ft/s)
Rock reaches ground when d(t)=0, i.e.
-16t^2-4t+382=0
t=-5.01 or t=4.763 seconds. reject negative root.

Therefore, domain, t=0 to 4.763 seconds
range = 0 to 382 ft

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Easton is going to invest $340 and leave it in an account for 8 years. Assuming the interest is compounded quarterly, what inter

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Answer:

100.7%

Step-by-step explanation:

Since the interest is compounded quarterly, and there are 4 quarters per year, that would leave us with 32 quarters total where interest is acquired. Now, we need to find the interest rate, that would be required in order to end up with 420 dollars after 32 quarters.

We can setup a formula using our period of time and the money he invested into the bank:

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