#integrate e^(-t/(1-sin(2x))) wrt x from 0 to pi/4
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teaset
t real positive
yes
i have tried the change of variables $u = \frac{t}{1-\sin2x}$ but it led me nowhere
also tried wolfram alpha / mathematica and the results are series expansions which i am not after
teaset
which lead me to a more complicated integrand so i did not dig it thru much
$$ \frac{d}{dt} \left( \int_{a}^{b} h(x,t) , dx \right) = \int_{a}^{b} \frac{\partial}{\partial t} h(x,t) , dx $$
try this maybe
the derivative just needs to exist in this case, which it does
Latias
yes in that case the integrand is more complicated
so the t ahould be an X?
no
where does this integral come?
what do you mean?
wait i actually got an idea
i want to ask smthing are limits of the integral correct?
like are they really 0 to pi/4?
it could help if you told where does this integral comes from
only significant things i have uncovered from this integral are the following:
$$\int_0^{\pi/4}e^{-\frac{n}{2sin^2(x)}}dx$$
T4nuk1
from this you can get various integrals each as difficult to evaluate as the last one
something that came to my mind while doing this were the fourier transforms and fourier functions but the integral limit's don't coincide
but idk
it occured to me cus the function is pi periodic
also
this came up
one can obtain $$1/2\int_0^{\infty}\frac{1}{(x+2)\sqrt{x+1}}e^{-\frac{n(x+2)}{2}}dx$$
wich is soooo similar to the $$R_C(x,y)$$
so for n=0
one gets that special case
also if you let $$f(n)=1/2\int_0^{\infty}\frac{1}{(x+2)\sqrt{x+1}}e^{-\frac{n(x+2)}{2}}dx$$
T4nuk1
$$\forall n\ge0\ , 0\leq{f(n)}\leq \pi/4$$
T4nuk1
idk it will be kind of hard to actually do this one
waaaaaaaaaaaaaaait
i got smthing
so this can be also seen as the laplace transfor of the derivatice of the arctan(sqrt(x+1))
now those limits in the first term change depending on n
cus on n=0
that term is just pi/4
for n aproach to infinity it goes to 0
and everything in between it goes to -pi/4
i think
although i think i saw something similar elsewhere
again it would be nice to know from where does this integral comes from
uh
ur math looks ok, haven't thought about integration by parts but still we have this second term
i got it as an intermediate step of something im working on
oh
i'll dm u
||"solution" based off of qfunction; use substitution t/(1-sin2x) = x^2 and gradshteyn 4th edition 3.468 1||
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