Answer:
5 km/h
Step-by-step explanation:
In this problem, Lashonda swam 4 km against the current. So the distance covered in this case is
Calling 
the velocity of Lahonda without the current, and 
the velocity of the current, in this situation Lahonda's velocity is
So we can write:
where 
is the time taken to cover the distance.
When Lashonda swims with the current, her velocity is
So we can write
where
is the distance covered in this case, and 
the time taken.
The velocity of the current is
Since Lashonad takes the same time to cover the two distances,
So we can write
And solving for v, we find Lashonda's velocity without the current:
We're looking for a solution of the form
with derivatives
Substituting these into the ODE gives
Shifting indices to get each term in the summand to start at the same power of 
and pulling the first few terms of the resulting shifted series as needed gives
Then the coefficients in the series solution are given according to the recurrence
Given the complexity of this recursive definition, it's unlikely that you'll be able to find an exact solution to this recurrence. (You're welcome to try. I've learned this the hard way on scratch paper.) So instead of trying to do that, you can compute the first few coefficients to find an approximate solution. I got, assuming initial values of 
, a degree-8 approximation of
Attached are plots of the exact (blue) and series (orange) solutions with increasing degree (3, 4, 5, and 65) and the aforementioned initial values to demonstrate that the series solution converges to the exact one (over whichever interval the series converges, that is).
I believe it’s D !
hope this helped
Hey! Statement 1 is false because the domain of f is all real numbers since the function is quadratic.
Statement 2 is true.
Statement 3 is true because when we graph f, it is a parabola opening upwards with vertex (3, -1). Since it is opening upward, then the value of x from -∞ to 3 is decreasing while increasing from 3 to ∞.
Statement 4 is false because we just stated above that f is decreasing from -∞ to 3. Hence, f is also decreasing from -1 to 3. Hence, f is not increasing from -1 to ∞.
Statement 5 is false because the axis of symmetry is x = 3.
Statement 6 is true.
Hope this helps! :)
Answer:
Answer choice A(57%)
Step-by-step explanation:
The margin of error is 7%. This means the 63% could either 7% too high or 7% too low. Answer choice A is the only answer choice that is within the range of percents that it could possibly be(between 56% and 70%). Answer choice B is 10% off, 3% out of the range. Answer choice C is 25% off, 18% out of the range. Answer choice D is 32% off, 24% out of the range. Hope this helps. :)
