sec(arccos(-3/5))

解答

sec (arccos (- \frac{3}{5}))

- \frac{5}{3}

十进制

- 1.66666 \dots

求解步骤

sec (arccos (- \frac{3}{5}))

使用三角恒等式改写:

sec (arccos (- \frac{3}{5})) = \frac{1}{( - \frac{3}{5} )}

利用以下特性:

sec (arccos (x)) = \frac{1}{x}

= \frac{1}{( - \frac{3}{5} )}

= \frac{1}{- \frac{3}{5}}

化简

= - \frac{5}{3}

6 sin (1 0^{\circ})

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