All Questions
7
questions
0
votes
1
answer
227
views
Is there any way to circumference of a circle with radius but without pi? [closed]
Please let me know if anybody knows how to calculate the circumference of a circle with radius but without pi?
0
votes
5
answers
256
views
Possibility of finding exact value of circle area
I am taking a Calculus course and my current theme is calculating a circle's area from scratch, and the tutor is splitting the circle in smaller circle shapes, draws them as a rectangle and putting ...
- 109
2
votes
2
answers
149
views
Geometric Approximation for Area of Circle Using Calculus
A couple of years ago, I came up with this formula:
$$\lim_{n\to\infty}\frac{180\left(\pi^2r^2\cot\left(\frac{180}{n}\right)\right)}{n\pi}=\pi r^2$$
I derived it from a geometric perspective and just ...
- 1,030
1
vote
2
answers
9k
views
find the point (x,y) on the unit circle that corresponds to the real number t
t=π/4
I tried to solve this problem but i dont even know where to start! i thought you had to divide the pie into 4 then put it on a number line, but when i checked my answer it was like in quadratic ...
- 11
5
votes
2
answers
359
views
Geometric Identities involving $π^2$
Are there any known geometric identities that have $π^2$ in the formula?
- 1,844
3
votes
1
answer
270
views
What does Spivak want me to do?
This goes on in Chapter 8, on least upper bounds and related topics. I have proven $(a),(b),(c)$.
The sketch is.
$(a)$ If $\{a_n\}$ is a sequence of positive terms such that $$a_{n+1}\leq a_n/2$$ ...
- 123k
7
votes
9
answers
25k
views
Calculate $\pi$ precisely using integrals?
This is probably a very stupid question, but I just learned about integrals so I was wondering what happens if we calculate the integral of $\sqrt{1 - x^2}$ from $-1$ to $1$.
We would get the surface ...
- 1,283