Questions Asked

PhoenixFire:
Group Title
What is the spherical equation for the sphere located at (0, 0, 1) with a radius of r=1?
 updated one year ago
 1 reply
 No Medals Yet

PhoenixFire:
Group Title
Equation of a sphere in Spherical Coordinates.
Is there a general form for this?
…
 updated one year ago
 No Medals Yet

PhoenixFire:
Group Title
A little tip: If you find some math thing done in \(\LaTeX\) you can Rightclick it and choose "Show Math As" then click "TeX Commands"
This…
 updated 2 years ago
 3 replies
 3 Medals

PhoenixFire:
Group Title
I saw this a little while ago and wanted to figure out how to prove that it's invalid.
\[1+2+4+8+...+\infty= 1\]
Proof is as follows:…
 updated 2 years ago
 7 replies
 1 Medal

PhoenixFire:
Group Title
How do you find the derivative of
\[{cos(x)}^{cos(x)}\]
 updated 2 years ago
 9 replies
 2 Medals

PhoenixFire:
Group Title
Prove by induction that \[(A_1A_2...A_n)^{1}={A_n}^{1}...{A_2}^{1}{A_1}^{1} \]\[\forall n\in \mathbb{N}\] and A_i for i=1, 2, ... are in…
 updated 2 years ago
 20 replies
 2 Medals

PhoenixFire:
Group Title
How do I find the lifetime of a component with reliability function: \[R(t)=e^{0.01t}\]
I calculated the probability density function: \[f(…
 updated 2 years ago
 5 replies
 No Medals Yet

PhoenixFire:
Group Title
Use elementary row operations to find the inverse of \left[\begin{matrix}2 & 1 & 3 \\ 4 & 2 & 1 \\ 0 & 4 & 2\end{matrix}\right]
I kno…
 updated 2 years ago
 17 replies
 3 Medals

PhoenixFire:
Group Title
Does anyone know how to calculate how many times a ball will bounce if dropped from some height?
Information:
Restitution = 0.85
…
 updated 2 years ago
 56 replies
 2 Medals

PhoenixFire:
Group Title
How do you calculate the momentum of two objects immediately after a perfectly elastic collision?
Do you need to find the velocities of the…
 updated 2 years ago
 4 replies
 No Medals Yet

PhoenixFire:
Group Title
A horizontal spring with constant k=1200 and mass 10kg attached to the end. The mass is on a horizontal frictionless surface.
Question: How …
 updated 2 years ago
 22 replies
 1 Medal

PhoenixFire:
Group Title
Ball mass = 0.7kg dropped vertically from height 10m. Ball is observed to bounce a number of times before coming to rest. Coefficient of res…
 updated 2 years ago
 No Medals Yet

PhoenixFire:
Group Title
Is there a way to get the equation editor while posting a new question?
 updated 2 years ago
 No Medals Yet

PhoenixFire:
Group Title
Using mathematical induction prove that for \[ {n \ge 1} \in \mathbb{Z} \]
\[ 3^{2k}1 \] is divisible by 8.
 updated 2 years ago
 22 replies
 2 Medals

PhoenixFire:
Group Title
Need help with a proof
The theory is: if 3 divides a^2 then 3 divides a.
Now, they ask for the contrapositive (p>q = ~p>~q), which will…
 updated 2 years ago
 2 replies
 No Medals Yet

PhoenixFire:
Group Title
Using the Law of Contrapositive give proof of the theorem: For any integers a,b if ab is odd then either a is odd or b is odd.
I tried an…
 updated 2 years ago
 16 replies
 1 Medal

PhoenixFire:
Group Title
Prove that if n2 is divisible by 4 then n^2  4 is divisible by 16.
 updated 2 years ago
 15 replies
 1 Medal

PhoenixFire:
Group Title
find dy/dx of y=(sin(x))^x
 updated 2 years ago
 10 replies
 1 Medal

PhoenixFire:
Group Title
When mixing a certain "alcoholic beverage" a barperson starts with a 10 litre solution of 20% alcohol. Into this solution the barperson mixe…
 updated 2 years ago
 3 replies
 No Medals Yet

PhoenixFire:
Group Title
When a charged capacitor is connected to earth, it discharges and the voltage V across it will decrease according to the equation:
dV/dt=−V…
 updated 2 years ago
 8 replies
 No Medals Yet
 < Newer questions