cos(x)=(-2)/5

Lösung

cos (x) = \frac{- 2}{5}

x = 1.98231 \dots + 2 πn, x = - 1.98231 \dots + 2 πn

Grad

x = 113.57817 \dots^{\circ} + 36 0^{\circ} n, x = - 113.57817 \dots^{\circ} + 36 0^{\circ} n

Schritte zur Lösung

cos (x) = \frac{- 2}{5}

Wende Bruchregel an:

\frac{- a}{b} = - \frac{a}{b}

cos (x) = - \frac{2}{5}

Wende die Eigenschaften der Trigonometrie an

cos (x) = - \frac{2}{5}

Allgemeine Lösung für

cos (x) = - \frac{2}{5}

cos (x) = - a \Rightarrow x = arccos (- a) + 2 πn, x = - arccos (- a) + 2 πn

x = arccos (- \frac{2}{5}) + 2 πn, x = - arccos (- \frac{2}{5}) + 2 πn

x = arccos (- \frac{2}{5}) + 2 πn, x = - arccos (- \frac{2}{5}) + 2 πn

Zeige Lösungen in Dezimalform

x = 1.98231 \dots + 2 πn, x = - 1.98231 \dots + 2 πn

sin (\frac{θ}{2}) = \frac{1}{m}

2 (cos^{4} (x) + 1 - sin^{4} (x)) = 3

csc (\frac{2 x}{3}) - 1 = 0

6 tan (x) = tan^{2} (x), x = 0

5 cos^{2} (x) + 3 cos (x) - 1 = 0