Respuesta :

Answer:

[tex]\dfrac{2}{5}\sqrt{3}+\dfrac{3}{10}[/tex]

Step-by-step explanation:

Trigonometric Identities

[tex]\sin (A \pm B)=\sin A \cos B \pm \cos A \sin B[/tex]

Trigonometric ratios

[tex]\sf \sin(\theta)=\dfrac{O}{H}\quad\cos(\theta)=\dfrac{A}{H}\quad\tan(\theta)=\dfrac{O}{A}[/tex]

where:

  • [tex]\theta[/tex] is the angle
  • O is the side opposite the angle
  • A is the side adjacent the angle
  • H is the hypotenuse (the side opposite the right angle)

Using the trig ratio formulas for cosine and sine:

  • [tex]\cos (\angle BAC)=\dfrac{12}{20}[/tex]
  • [tex]\sin (\angle BAC)=\dfrac{16}{20}[/tex]

Angles

[tex]\sin (30^{\circ})=\dfrac{1}{2}[/tex]

[tex]\cos (30^{\circ})=\dfrac{\sqrt{3}}{2}[/tex]

Therefore, using the trig identities and ratios:

[tex]\begin{aligned}\sin (\angle BAC + 30^{\circ}) & = \sin (\angle BAC) \cos (30^{\circ})+\cos (\angle BAC) \sin (30^{\circ})\\\\& = \dfrac{16}{20} \cdot \dfrac{\sqrt{3}}{2} + \dfrac{12}{20} \cdot \dfrac{1}{2}\\\\& = \dfrac{16}{40}\sqrt{3}+\dfrac{12}{40}\\\\& = \dfrac{2}{5}\sqrt{3}+\dfrac{3}{10}\end{aligned}[/tex]

sin<BAC

  • P/H
  • 16/20

cos<BAC

  • B/H
  • 12/20

NOw

  • sin(<BAC+30)
  • sin<BAC×cos30+cos<BACsin30
  • 16/20(√3/2)+12/20(1/2)
  • 2/5√3+3/10