cos(A)= 12/37

解

cos (A) = \frac{12}{37}

A = 1.24049 \dots + 2 πn, A = 2 π - 1.24049 \dots + 2 πn

度

A = 71.07535 \dots^{\circ} + 36 0^{\circ} n, A = 288.92464 \dots^{\circ} + 36 0^{\circ} n

解答ステップ

cos (A) = \frac{12}{37}

三角関数の逆数プロパティを適用する

cos (A) = \frac{12}{37}

以下の一般解

cos (A) = \frac{12}{37}

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

A = arccos (\frac{12}{37}) + 2 πn, A = 2 π - arccos (\frac{12}{37}) + 2 πn

A = arccos (\frac{12}{37}) + 2 πn, A = 2 π - arccos (\frac{12}{37}) + 2 πn

10進法形式で解を証明する

A = 1.24049 \dots + 2 πn, A = 2 π - 1.24049 \dots + 2 πn