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### Unexpected result for trigonometric function

I'm trying to solve the following trig eqn using sage.

$$sin(x)-cos(x) = 0$$

Hand calculation give me the result of: $$x=\frac{\pi}{4} + n\pi$$

However, the solve() method gives me a different result, why is that?:

sage:
sage: solve(sin(x)-cos(x) == 0, x, to_poly_solve=True)
[x == 1/4*pi + pi*z25]
sage:


Also, what's z in the answer? I haven't defined any such variable.

### Unexpected result for trigonometric function

I'm trying to solve the following trig eqn using sage.

$$sin(x)-cos(x) = 0$$

Hand calculation give me the result of: $$x=\frac{\pi}{4} + n\pi$$

However, the solve() method function gives me a different result, why is that?:

sage:
sage: solve(sin(x)-cos(x) == 0, x, to_poly_solve=True)
[x == 1/4*pi + pi*z25]
sage:


Also, what's z in the answer? I haven't defined any such variable.