Where am I going wrong in derivation of the following trig formula?
51829
How have the "following trig formulas" been modified to obtain the new trig formulas?
2676
Finding $\frac {d(\tan \theta)}{d\theta}$
61591
Solve simple trig equation
17769
Show that $\frac{\sin x}{\cos 3x}+\frac{\sin 3x}{\cos 9x}+\frac{\sin 9x}{\cos 27x} = \frac{1}{2}\left(\tan 27x-\tan x\right)$
41943
Why is it that when proving trig identities, one must work both sides independently?
125171
Help with this trigonometry problem?
108808
$x =r\cos \theta$ and $y = r\sin\theta$, determine $\frac{\partial r}{\partial x}$ and $\frac{\partial \theta}{\partial x}$
6140
Derivation of Ohm's Law
5747
$\cos(\arcsin(x)) = \sqrt{1 - x^2}$. How?
1957
Derivation of Kepler's laws
617
Find θ: $β=\arctan\frac{(R+r)·\sin(θ)-r·\sin(θ(1+\frac{R}{r}))}{(R+r)·\cos(θ)-r·\cos(θ(1+\frac{R}{r}))}$
77669
Limits of trig functions
68116
How to derive this version of variance formula
33396
Generalizing a Trig Identity
64255
Trigonometry problem
109913
Derivation of formula of normal acceleration
7306
How is the equation of motion on an ellipse derived?