u/wbld

Maclurin for sin(x)

f(x) = sin(x)

f'(x) = cos(x)

f''(x) = -sin(x)

f'''(x) = -cos(x)

f''''(x) = sin(x)

And this repeats forever.

f(0) = 0

f'(0) = 1

f''(0)=0

f'''(0)=-1

f''''(0)=0

And this repeats forever.

From here we can center a maclurin series at (a)? = 0 -> I cannot remember if its a or x

Using 5 points we can use

f(0) = 0

f'(0) = 1

f'''(0) = -1

f'''''(0) = 1

f'''''''(0) = -1

From here we can conclude (1) we are oscillating between - and +, (2) the points are always odd multiples of primes, and (3) since the even multiples of prime are 0, we can ignore these as they do not add value

The defintion of odd is defined as 2k+1, k element of the real

So

(-1)^(n)(x^(2k+1))/(2k+1)!

And we can add this at every n.

If we add this add every n we can think of an infinite sum

Since we are centered at (a?) = 0 the sum must start at 0.

To motivate convergence, we plug in known points of sin(x).

Must it be that if our sum at some n equals the function at the same x,

Out infinite sum converges for all x?

Let me know if i did justice for the maclurin of sin(x)!

Sorry posted via phone.... don't know how to use symbols here

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u/wbld — 11 days ago

is daily integral getting more complex?

Today's easy daily integral seems to be more complex than usual. I do not know what the Lambert W function is. Is this higher level mathematics? or was this something i missed in calculus? Usually, I am able to solve easy integrals. My initial thoughts were that the integral is 0 because this clearly is not easy, but then I looked at the bounds and realized, yeah, that probably does not equal 0.

https://preview.redd.it/crzmxwp7gxlh1.png?width=808&format=png&auto=webp&s=9d4cad76ab8e432c305d377420ad21b609de92ae

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u/wbld — 2 months ago

Prove the derivative

Hello, can someone use Epsilon delta to prove the derivative of x² is 2x

Please show all steps

Im curious on how derivatives are proved.

I know the formula defintion of a derivative is the limit as h approaches 0. I know that for limits you need to find a relationship for delta and epsilon.

I went through all of calculus never actually proving a derative using epsilon delta. Ever. I proved limits using epsilon delta. But a derative? Never.

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u/wbld — 3 months ago