Instrucciones: Responde las siguientes preguntas.

• Identifica la opción correcta.
  • $$\mbox{sen}^{2} 225^{\circ} + \cos^{2} 315^{\circ} = 2\mbox{sen} 60^{\circ} \mbox{sen} 30^{\circ}$$
  • $$\mbox{sen}^{2} 225^{\circ} + \cos^{2} 315^{\circ} = \cos 120^{\circ}$$
  • $$\mbox{sen}^{2} 225^{\circ} + \cos^{2} 315^{\circ} = 1$$
  • $$\mbox{sen}^{2} 225^{\circ} + \cos^{2} 315^{\circ} = 1+ \cos 300^{\circ}$$

• Identifica la opción correcta.
  • $$\mbox{sen} 60^{\circ} - \cos 60^{\circ} \tan 30^{\circ} = \sqrt{\frac{1+ \cos 300^{\circ}}{2}}$$
  • $$\mbox{sen} 60^{\circ} - \cos 60^{\circ} \tan 30^{\circ} = \frac{\mbox{sen} 150^{\circ}}{\mbox{sen}30^{\circ} \mbox{sen} 300^{\circ}}$$
  • $$\mbox{sen} 60^{\circ} - \cos 60^{\circ} \tan 30^{\circ} = \tan 30^{\circ}$$
  • $$\mbox{sen} 60^{\circ} - \cos 60^{\circ} \tan 30^{\circ} = 3\mbox{sen} 150^{\circ} - 4\mbox{sen}^{3} 30^{\circ}$$

• Identifica la opción correcta.
  • $$\cos 240^{\circ} = \mbox{sen}^{2} \left ( -60^{\circ} \right )$$
  • $$\cos 240^{\circ} = \tan 30^{\circ}$$
  • $$\cos 240^{\circ} = \sqrt{\frac{1+ \mbox{sen} 150^{\circ}}{2}}$$
  • $$\cos 240^{\circ} = \cos^{2} 60^{\circ} - \mbox{sen}^{2} 60^{\circ}$$

• Identifica la opción correcta.
  • $$\cos 30^{\circ} = \sqrt{\frac{1+ \cos 300^{\circ}}{2}}$$
  • $$\cos 30^{\circ} = \cos^{2} 60^{\circ} - \mbox{sen}^{2} 60^{\circ}$$
  • $$\cos 30^{\circ} = 1$$
  • $$\cos 30^{\circ} = \csc^{2} 330^{\circ}$$

• Identifica la opción correcta.
  • $$\csc 60^{\circ} - \tan 30^{\circ} = \csc^{2} 330^{\circ}$$
  • $$\csc 60^{\circ} - \tan 30^{\circ} = \mbox{sen}^{2} \left ( -60^{\circ} \right )$$
  • $$\csc 60^{\circ} - \tan 30^{\circ} = \tan 210^{\circ}$$
  • $$\csc 60^{\circ} - \tan 30^{\circ} = \sqrt{\frac{1+ \mbox{sen} 150^{\circ}}{2}}$$