Also the new function you make for the difference of the rates you why do you have to differentiate again as it is already the difference of the derivatives. Idk
@Frigidcold Actually, it asked for the “overflowing” part, not when it starts becoming overflowed. So you need inequality.
@chocomilk123 yeah they’re both 1.
Reviewing the questions on this forum makes me second guess myself on whether I put that answer LOL
@beavergod: I set the expression equal to 50 because it said the first time that it will equal it right???
But at t =8 where part d started the pipe did not have 30 in it that was at t=0
@sjwon3789 I’m pretty sure it asked for the time at which it will overflow, so equals sign is appropriate.
@Frigidcold hahaha my work was so sloppy, i kept making errors i was too lazy to re-write/erase so i just wrote over in darker pencil
@beavergod It was t equals 3 something because the water was at like 27. Also, you don’t differentiate again.
Lol semantics
@JuicyMango I did the same but did not include the initial condition as that was only at t=0 not t=8
@beavergod: you have to add 30 to all of the min values for the pipe because that was the initial amount.
@synack: i got the integral from 8 to w because it said after 8…i though???
@picarat: did u have form o? those look familiar to me as other answer choices that i didnt pick lol. Done you first find the derivative of ln(x) which is 1/x then just plug in 2e so its 1/2e???
When it asked for a min did anyone get like at t=3.27 I forget whether this is the parametric problem or the water one
@beavergod Can’t k also be -5 because critical point means the denominator is 0, undefined? I put it after -10 and I hear the AP rule is that they take the first one so hopefully…
@sjwon3789 Sorry to say, you may be in the wrong here. Everyone from my school and everyone in this forum seem to believe it was the time it started to overflow. The question specifically asked for an equation, not an inequality.
@JuicyMango I’m pretty sure you have to take the integral starting from 0, because otherwise you assume that it’s 30 at t=8 rather than 30 at t=0.
Um well the function is undefined when the denom is equal to 0 but I’m not sure if they would accept both @sjwon3789
@synack But if it were equal, that means it’s perfectly at 50, not overflow. Am I wrong??
And ya integral was 8 to w for the part d of the water pipe
I remember distinctly wondering whether to put an inequality or an equals sign, but then I noticed that it said “when the pipe STARTED to overflow” so I used an equals sign. However, I would say either is appropriate because you trying to find that w point, which can be solved using either an inequality or equals sign. I think the main point of the question was to make sure you could set up your integral as 30 + whatever your integral was of R(t) - D(t) bounded by 0 and 8 + integral of R(t) - D(t) between 8 and your w, and that would equal (or use inequality) 50.
I really liked the integration by partial fractions problem, that was good, also, I have an ambiguity issue on one of the FRQs, it wanted the tangent line to a parametric curve, but it didn’t say which curve, I assumed it was to the position curve, but I don’t know.