All Questions
5
questions
0
votes
1
answer
66
views
Maximum and Minimum of a cubic function
Maximum value of function
$y = x^3-5x^2+2$
a) 5
b) $\infty$
c) 2
d) -5
We know to find maximum value of a function we take first derivative of the function and make it zero and get some point. And ...
- 185
4
votes
6
answers
693
views
Is $x^3$ really an increasing function for all intervals?
I had an argument with my maths teacher today...
He says, along with another classmate of mine that $x^3$ is increasing for all intervals. I argue that it isn't.
If we look at conditions for ...
- 45
1
vote
0
answers
72
views
How units didn't change while differentiation?
In this example, rate of change has units cm², while the original quantity, area, also has same units. I learnt that units change just like normal ratio, that is dA/dr will have same units as A/r, so ...
- 61
0
votes
0
answers
48
views
Find a function
It's a cuttout from Rempe article "A mathematical model of the sleep/wake cycle" about a function which I don't understand how to describe: $h(t)$ decays exponentially while the system is asleep
and ...
- 480
0
votes
2
answers
1k
views
Finding maximum of convex function (appliance of derivatives)
The task goes as following:
Divide the length of $14$ into parts $a$ and $b$, in a way that the sum of surfaces of two squares (which sizes are $a$ and $b$), is minimal.
$14=a+b => b=14-a$ $....(...
- 657