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## Activity overview

• 20leunge commented,

Here's how I see it. Let x represent the time Rob intended to spend on the project. However, he spent 100% of that times AND 25% more, so 125% of the planned time. So the time Rob actually spent wa...

• 20leunge commented,

RowanH: In general, |x|+|y| ≠ |x+y|. Consider x = 1, y = -1. |x|+|y| = 2 |x+y| = 0.  So. |x|+|y| ≠ |x+y| because 2 ≠ 0. zineb.aj: I'm not sure why you wouldn't want to remove the absolute value sym...

• 20leunge commented,

First, solve x^2=a^2. Take the plus and minus square root of both sides. The negative root is needed because when that is squared on both sides, you still get back the original equation. ==> x=a...

• 20leunge commented,

All four solutions: x=2, x=3, x=((-1+sqrt(17))/2), x=((-1-sqrt(17))/2). You have to solve for 3x-5=((x-1)^2) and 3x-5= - ((x-1)^2) because of the absolute value sign on the 3x-5. Plugging in the so...

• 20leunge commented,

Just looking at the partial derivative with respect to x, I believe the chain rule is being applied to Q, and then to R along with the product rule. The chain rule is being used because z is itself...

• 20leunge commented,

I would say differential calculus.

• 20leunge commented,

What I did was I skipped this part and continued learning until I finished the combinatorics section from Precalculus. Then, I went back and learned it. It's not exactly a recurring topic throughou...

• 20leunge commented,

I imagine you would have to use the Lambert W function, but I'm not familiar with it.

• 20leunge commented,

If you know the mass of water lost, you can calculate using stoichiometry the moles of water. Oxygen has a molar mass of 16.00 grams per mole (g/mol) and hydrogen has a molar mass of 1.01 g/mol. In...

• 20leunge commented,

Nitrogen has 5 valence electrons, so NH3 will have 8 valence electrons total.

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