Respuesta :

1/12π

9) Considering that the reference angle is an acute angle, (less than 90º or

π/2) then we can write out (in degrees to make it easier to grasp it then in π radians):

[tex]-\frac{47\pi}{12}=-705^{\square}[/tex]

So we can subtract 360º, 705º-360º= 345º. Subtracting once more:

360º-345º = -15º. Writing that in Pi radians we've got:

[tex]\begin{gathered} -\frac{47\pi}{12}+2\pi=-\frac{23\pi}{12} \\ -\frac{23\pi}{12}+2\pi=\frac{1}{12}\pi \end{gathered}[/tex]

2) Recap:

• Check if the angle is greater than 360º (or 2π) If it is so you can subtract it from 360º(2π)

• As in this case, 345º is in the Quadrant IV, then we'll subtract it again from 360º.

,

• Since the given angle is negative (Counterclockwise) then we add to perform that subtraction again: 360-345 = 15º or 2π -23/12 π = 1/12π

3) Hence, the answer is 1/12π