Úlohy: 1–2 / 2

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1. Goniometrické rovnice 2

Vyřešte goniometrické rovnice:
a)   \[ \sin x = \frac{1}{2} \]
b)   \[ \cos x = -\frac{\sqrt{3}}{2} \]
c)   \[ \tan x = 1 \]
d)   \[ \sin 2x = 0 \]
e)   \[ 2\cos^2 x - 1 = 0 \]
f)   \[ \sin^2 x = \frac{1}{4} \]
Řešení
a)   \[ x = \frac{\pi}{6} + 2k\pi, \, x = \frac{5\pi}{6} + 2k\pi \]
b)   \[ x = \frac{5\pi}{6} + 2k\pi, \, x = \frac{7\pi}{6} + 2k\pi \]
c)   \[ x = \frac{\pi}{4} + k\pi \]
d)   \[ x = \frac{k\pi}{2} \]
e)   \[ x = \frac{\pi}{4} + 2k\pi, \, x = \frac{3\pi}{4} + 2k\pi, \,\]\[x = \frac{5\pi}{4} + 2k\pi, \, x = \frac{7\pi}{4} + 2k\pi \]
f)   \[ x = \frac{\pi}{6} + 2k\pi, \, x = \frac{5\pi}{6} + 2k\pi, \,\]\[x = \frac{7\pi}{6} + 2k\pi, \, x = \frac{11\pi}{6} + 2k\pi \]
Matematická úloha – Goniometrické rovnice 2

2. Goniometrické rovnice 1

Vyřešte goniometrické rovnice:
a)   \[\sin x = \frac{1}{2}\]
b)   \[\cos x = -\frac{\sqrt{2}}{2}\]
c)   \[\tan x = \sqrt{3}\]
d)   \[\sin^2 x = \frac{3}{4}\]
e)   \[\cos 2x = 0\]
f)   \[\tan^2 x = 3\]
Řešení
a)   \[x = \frac{\pi}{6} + 2k\pi \lor x = \frac{5\pi}{6} + 2k\pi, k \in \mathbb{Z}\]
b)   \[x = \frac{3\pi}{4} + 2k\pi \lor x = \frac{5\pi}{4} + 2k\pi, k \in \mathbb{Z}\]
c)   \[x = \frac{\pi}{3} + k\pi, k \in \mathbb{Z}\]
d)   \[x = \frac{\pi}{3} + 2k\pi \lor x = \frac{2\pi}{3} + 2k\pi \lor x = \frac{4\pi}{3} + 2k\pi \lor x = \frac{5\pi}{3} + 2k\pi, k \in \mathbb{Z}\]
e)   \[x = \frac{\pi}{4} + \frac{k\pi}{2}, k \in \mathbb{Z}\]
f)   \[x = \frac{\pi}{3} + k\pi \lor x = -\frac{\pi}{3} + k\pi, k \in \mathbb{Z}\]
Matematická úloha – Goniometrické rovnice 1
 
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