(ii) \( 8^{2}=5^{2}+5^{2}-2(5)(5) \cos \beta \) \( \cos \beta \)

\( \operatorname { coti } x + \operatorname { cosec } x = 11 \)

A pylon \( \$ \$ 23.7 \$ \$ \mathrm{~m} \) high casts a shadow \( \$ \$ 46.8 \$ \$ \mathrm{~m} \) long. Determine the angle of elevation of the sun to the nearest tenth of a degree. 23.7 m high casts a shadow 46.8 m long. Determine the angle of elevation of the sun to the nearest tenth of a degree. Show answer

(d) Quando fazemos determinaçōes experimentais de uma grandeza \( X \), representamos seu valor numérico final acompanhado do erro \( \Delta X \) associado à medida, na forma \( X \pm \Delta X \). Para calcularmos o valor de uma funçāo \( f(X \pm \Delta X) \), utilizamos a regra \[ f(X \pm \Delta X)=f(X) \pm f^{\prime}(X) \Delta X \] Obtenha as fórmulas referentes a (i) \( \sin (X \pm \Delta X) \) e (ii) \( \cos (X \pm \Delta X) \)

3- Sabendo que \( \operatorname{cotag} 40^{\circ}=1,1918 \) e \( \cos 43^{\circ}=0,7314 \), determine. a) \( \operatorname{Cotag} 320^{\circ}= \) b) \( \cos 223^{\circ}= \)

\( \operatorname{Csc} 82.4^{\circ}= \) Blank 1 Express your answer in 3 decimal points.