# mathematic

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astrophysics
1. ## Which galaxies will become gravitationally bound to us after our collision with Andromeda?

Since both galaxies are mostly empty space, it is difficult to predict what happens when they meet.
2. ## Quantum gravity idea

For a physical theory to be taken seriously, it must be backed up with observation information. Have you done anything like this?
3. ## A Brand New Approach

What is the purpose of this?
4. ## Oldest spiral galaxy challenge to established age of universe?

2.8 billion years is a long time.
5. ## Best way to solve this system of equations?

Matrix is probably the best way. Use a calculator.
6. ## Need opinion on project

I suggest you look at energy storage, such as better batteries, molten salt, etc.
7. ## Determine the solution to the following differential equation: dA/dt = -0.3A and A(2) = 400

This is a standard elementary d. e. Solution uses dA/A=-0.3dt, which integrates to ln(A)=-0.3t+C or A=Ke^(-0.3t). Plug in boundary condition to get K.
8. ## Statistics in the land of the Leprachaun

Look closely at the offending ball. There is a small white circle covering part of the 8, so it looks like a 3.
9. ## Differentiability of the acceleration

Your development has x as a function of something, so that you get x'=v. In order to answer your question you need an explicit statement of the dependence of x or v on the something (time?).
10. ## Acceleration Question

Basic equation: v=v_0+at and solve for t. v=0 (stop), v_0=30, a= -10. For the second question v_0=60. To get distance traveled, integrate v(t) from time t=0 to time t=stop.