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9h
comment Trigonometric equality to prove
Probably mathworld.wolfram.com/WernerFormulas.html should help
9h
comment Trigonometric AP relation on sides of a triangle
@user3650050, How about this?
10h
comment Using Wilson's Theorem to prove Fermat's Little Theorem
See also : math.stackexchange.com/questions/234745/…
1d
comment Hard Trigonometric Equation
@ReneSchipperus, Do you have a deterministic way to solve such a Transcendental equation (en.wikipedia.org/wiki/Transcendental_equation). How do you establish the uniqueness?
1d
comment Conditional identity based proof
math.stackexchange.com/questions/393786/…
1d
comment Hard Trigonometric Equation
math.stackexchange.com/questions/75825/…
1d
comment A kind of a remainder problem
@DhruvGoel, math.stackexchange.com/questions/12067/…
1d
comment How to find angle x without calculator?
@ComplexGuy, Consider $$\triangle CAD$$
1d
comment Infinitely many prime numbers 6n-1
math.stackexchange.com/questions/407259/…
1d
comment When is $n!+1$ composite?
en.wikipedia.org/wiki/Factorial_prime , Check for $n=27,77,154$ etc.
2d
comment Trigonometric AP
@user3650050, math.stackexchange.com/questions/877784/…
2d
comment Find $\sin(x+y)$, given $\tan x$ and $\cos y$
@user159676, What is $$\sqrt{25}?$$
2d
comment Why is $\sin 30^\circ=\frac{1}{2}$
meritnation.com/ask-answer/question/…
2d
comment Find $\sin(x+y)$, given $\tan x$ and $\cos y$
You are actually done at $$\frac{\sqrt3-2}{2\sqrt5}$$ Optionally we can rationalize the denominator to get $$\frac{\sqrt{15}-2\sqrt5}{10}$$
2d
comment Length of smallest repunits divisible by primes
This can be generalized for integer $n$ with $(30,n)=1$ If $\displaystyle n|\underbrace{11\cdots11}_{m\text{ digits}}\iff n|\underbrace{9\cdots99}_{m\text{ digits}}=(10^m-1)$ Now, the smallest positive value of $m=$ord$_n(10)$
2d
comment Trigonometry, eliminate theta
@chaya, How about this?
2d
comment Prove that every non-prime natural number $ > 1$ can be written in the form of $n+(n+2)+(n+4)+…+(n+2m) = p$
So, $$p=(m+1)(m+n)$$
2d
comment How to figure out the solution to this equality problem?
@Shine, There is a typo inside the last parenthesis
2d
comment Trigonometry Compund Angles Problem
mathworld.wolfram.com/ProsthaphaeresisFormulas.html
2d
comment Eliminate variable in trigonometry equations
Can we start with $$2\psi+\theta=\psi+(\psi+\theta)$$ and solve for $\sin(\psi+\theta),\cos(\psi+\theta)$