# Trigonometry. sinus

• Jan 3rd 2010, 08:25 AM
jeunesse27
Trigonometry. sinus
Please, help me to figure this one out.
Appreciate your help =) Happy new year!

Approximate, to the nearest 0.1 degree, all angles (theta) in the interval [0, 360) that satisfy the equation sin (theta)=0.2548
there might be more than one answer
• Jan 3rd 2010, 08:53 AM
skeeter
Quote:

Originally Posted by jeunesse27
Please, help me to figure this one out.
Appreciate your help =) Happy new year!

Approximate, to the nearest 0.1 degree, all angles (theta) in the interval [0, 360) that satisfy the equation sin (theta)=0.2548
there might be more than one answer

since $\displaystyle \sin{\theta} = 0.2548 > 0$ , then two solutions for $\displaystyle \theta$ exist in the given interval ... one in quadrant I and the other in quadrant II.

get out your calculator, make sure it is in degree mode, and calculate the following ...

$\displaystyle \theta = \sin^{-1}(0.2458)$

$\displaystyle \theta = 180 - \sin^{-1}(0.2458)$

$\displaystyle \sin^{-1}$ is the inverse sine function on your calculator.