Solving $\tan(x+1)-\tan(x)=0$

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How do we find $x$ for this equation? $$\tan(x+1)-\tan(x)=0$$

I tried Newton's method, but I think my initial guess is not appropriate. I started with $x=1/2$, but I failed to end up with the approximated solution. What would the best initial guess be for this problem? Thanks!

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There are 3 best solutions below

0
On

$$\tan(x+1)-\tan{x}=\frac{\sin1}{\cos{(x+1)}\cos{x}}$$ and since $\sin1\neq0$, we see that our equation has no solutions.

1
On

The graph of $y = \tan(x+1)$ is identical to that of $y=\tan x$, except shifted leftward by one unit. Given their asymptotic nature, these graphs "obviously"(?) never meet.

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0
On

Another attempt..

1)$ y= \tan(x) $, $-π/2 \gt x \lt π/2.$

The function is strictly monotonically increasing in this interval, I.e.

for $-π/2 < x < x+1 \lt π/2$.

No solution.

2) Let $x = π/2 -\epsilon$, with

$0\lt \epsilon \lt 1,$ then $x+1 > π/2.$

We have:

$\tan(x)>0$, and $\tan(x+1)<0.$

No solution.

3) Similarly for $x < - π/2 $, and $x+1 > -π/2.$

4) The case $x \in (kπ -π/2, kπ +π/2)$, $k \in \mathbb{Z}$,

can be reduced to one of the cases 1)-3),

since $\tan(x+kπ) = \tan(x)$.

The equation has no solution.