As a follow up for : https://www.physicsforums.com/threads/let-k-n-show-that-there-is-i-n-s-t-1-1-k-i-1-2-k-i-1-4.1054669/
show that ## \alpha\left(k\right)\ :=\ \left(1-\tfrac{1}{k}\right)^{\ln\left(2\right)k}-\left(1-\tfrac{2}{k}\right)^{\ln\left(2\right)k} ## is decreasing for ##...
Please walk me step by step on how to do it (we don't have imaginary numbers so don't bring that up)
Also how to put signs on the numbers line when I get minus in the root? (non solveable equation)
Sorry for my English.
For this,
I first try to work out where function is increasing
My working is
##f'(x) = 12x^3 - 12x^2 - 24x##
For increasing,
##12x(x^2 - x - 2) > 0##
##12x > 0## and ##(x - 2)(x + 1) > 0##
##x > 0## and ##x > 2## and ##x > -1##
However, how do I combine those facts into a single domain...
The answer key states that the new tangential speed is half the original speed. However, this isn't correct right? It should double.
My proof:
##F_c = \frac {mv^2} R##
##F_c = F_t##
##\frac {mv^2} {\frac R 4} = \frac {m(2v)^2} R## If centripetal force were to stay constant.
As such, tangential...
I don't understand part (c) the answer is decreasing for both. I would have it decreasing for the centripetal acceleration and then increasing for the velocity, why is that not correct?
Thanks in advance!
What are intervals of which the function $g(t)=3t^2-5t+1$
a. find the vertex convert to vertex form $g(t)=a(t-h)^2-k$
\item $g(t)=3\left(t-\dfrac{5}{3}t+\left(\dfrac{5}{6}\right)^2\right)
+1-\dfrac{25}{12}
=3\left(t-\dfrac{5}{6}\right)^2-\dfrac{13}{12}$
b. the parabola opens up and the vertex is...
Hello, I don't know to solve this exercise:
Let $\mathcal{B}_\mathbb{R}$ the $\sigma-algebra$ Borel in $\mathbb{R}$ and let $\mu : \mathcal{B}_\mathbb{R} \rightarrow{} \mathbb{R}_{+}$ a finite measure. For each $x \in \mathbb{R}$ define
$$f_{\mu} := \mu((- \infty,x]) $$
Prove that:
a)...
Problem: Find the cardinality of the set ## A = \{f \in \Bbb N \to \Bbb N. \forall n\leq m .f(n) \geq f (m) \} ##.
I know that ## A \subseteq P(\Bbb N \times \Bbb N) ## implies ## |A| \leq |P(\Bbb N \times \Bbb N)| = | P(\Bbb N) | = \aleph ##. So I have a feeling that ## \aleph \leq |A| ##...
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I want to know what is the incresing and decreasing interval of this even function $|e^x+e^{-x}|?$
If any member knows the correct answer, may reply to this question.
I am developing a market trade bot and need to extract some parameters from market data but I don't have idea how to do it exactly. need your help.
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hi,
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decreasing the resistance increases the current if the voltage remains unchanged.
Homework Equations
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Homework Statement
Hi everyone,
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https://imgur.com/a/vEIkg
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Homework Statement
Hi everyone,
8th grade physics teacher here.
We are doing a handout where we have to identify time-velocity graphs with descriptions. Can you help me with this one?
https://imgur.com/a/vEIkg
A) The velocity is increasing at a uniform rate.
B) The velocity is decreasing at...
Hiya everyone,
Alright ?
I have a simple theoretical question. In a decreasing geometric series, is it true to say that the ratio q has to be 0<q<1, assuming that all members of the series are positive ? What if they weren't all positive ?
Thank you in advance !
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