Question 1031958
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He all, Can somebody explain me the reason why for this equation:

tan(10° - 4x) = -1/sqrt(3)

the proposed solution is x=10°-k45° and not x=10°-k180°

This brings to the following 8 results in the first round of 360°:
10°, 55°, 100°, 145°, 190°, 235°, 280°, 325°
What causes this coeff k45° to be applied?
Thank you very much and regards
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<pre>
tan(10° - 4x) = {{{-1/sqrt(3)}}}   --->

10° - 4x = -30° + k*180°         (I wrote " + k*180° ", since 180° is the period of the tangent function).

From this equation we have 

4x = 40°  - k*180°,  k = 0, +/-1, +/-2, . . . 

and hence

x = 10° - k*45°,  k = 0, +/-1, +/-2, . . . 
</pre>