cos(x)= 1/6

解

cos (x) = \frac{1}{6}

x = 1.40334 \dots + 2 πn, x = 2 π - 1.40334 \dots + 2 πn

度

x = 80.40593 \dots^{\circ} + 36 0^{\circ} n, x = 279.59406 \dots^{\circ} + 36 0^{\circ} n

解答ステップ

cos (x) = \frac{1}{6}

三角関数の逆数プロパティを適用する

cos (x) = \frac{1}{6}

以下の一般解

cos (x) = \frac{1}{6}

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

x = arccos (\frac{1}{6}) + 2 πn, x = 2 π - arccos (\frac{1}{6}) + 2 πn

x = arccos (\frac{1}{6}) + 2 πn, x = 2 π - arccos (\frac{1}{6}) + 2 πn

10進法形式で解を証明する

x = 1.40334 \dots + 2 πn, x = 2 π - 1.40334 \dots + 2 πn