csc(θ)=(sqrt(13))/2 ,sec(θ)=(sqrt(13))/3

解答

csc (θ) = \frac{13}{2}, sec (θ) = \frac{13}{3}

θ \in R 无解

求解步骤

csc (θ) = \frac{13}{2}, sec (θ) = \frac{13}{3}

使用反三角函数性质

csc (θ) = \frac{13}{2}

csc (θ) = \frac{13}{2}

的通解

csc (x) = a \Rightarrow x = arccsc (a) + 2 πn, x = π - arccsc (a) + 2 πn

θ = arccsc (\frac{13}{2}) + 2 πn, θ = π - arccsc (\frac{13}{2}) + 2 πn

θ = arccsc (\frac{13}{2}) + 2 πn, θ = π - arccsc (\frac{13}{2}) + 2 πn

在

sec (θ) = \frac{13}{3}

范围内的解

θ \in R 无解

4 cos^{2} (x) + cos (2 x) - 7 cos (x) = - 2, 0^{\circ} \leq x \leq 36 0^{\circ}

tan (x) = \frac{25}{10}

\frac{26.4575}{sin ( 6 0 ^{\circ} )} = \frac{20}{sin ( B )}

sin (\frac{5}{2} θ) = - 0.966

sin^{2} (x) - \frac{2}{3} = 0