Use a calculator to approximate the degree measure (to 1 decimal place) or radian measure (to at least 4 decimal places) of the angle [tex]$\theta$[/tex] subject to the given conditions. Round all intermediate calculations to 1 decimal place.

Given:
[tex]$
\sin \theta = \frac{11}{17} \text{ and } 90^{\circ} \ \textless \ \theta \ \textless \ 180^{\circ}
$[/tex]



Answer :

To find the angle [tex]\(\theta\)[/tex] given that [tex]\(\sin \theta = \frac{11}{17}\)[/tex] and [tex]\(90^\circ < \theta < 180^\circ\)[/tex], follow these steps:

1. Find the sine of the angle:
[tex]\[ \sin \theta = \frac{11}{17} \approx 0.6471 \][/tex]

2. Calculate the reference angle:
Since [tex]\(90^\circ < \theta < 180^\circ\)[/tex], [tex]\(\theta\)[/tex] is in the second quadrant where [tex]\(\sin\)[/tex] is positive. The reference angle can be found using the inverse sine function (arcsine):
[tex]\[ \theta_{\text{ref}} = \sin^{-1}(0.6471) \][/tex]
Without a calculator, this step would typically be done using tables or inverse function properties, but for this detailed solution, let's directly state the value:
[tex]\[ \theta_{\text{ref}} \approx 40.3^\circ \][/tex]

3. Adjust for the second quadrant:
Since the angle is in the second quadrant, we have:
[tex]\[ \theta = 180^\circ - \theta_{\text{ref}} \][/tex]
Given [tex]\(\theta_{\text{ref}} \approx 40.3^\circ\)[/tex],
[tex]\[ \theta \approx 180^\circ - 40.3^\circ = 139.7^\circ \][/tex]

4. Convert the degree measure to radians (at least 4 decimal places):
We know [tex]\(180^\circ\)[/tex] corresponds to [tex]\(\pi\)[/tex] radians. So, to convert [tex]\(139.7^\circ\)[/tex] to radians:
[tex]\[ \theta_{\text{radians}} = 139.7^\circ \times \frac{\pi}{180^\circ} \][/tex]
Plugging in the numbers:
[tex]\[ \theta_{\text{radians}} \approx 139.7 \times \frac{\pi}{180} \approx 2.4379 \, \text{radians} \][/tex]

To summarize, the angle [tex]\(\theta\)[/tex]:
- In degree measure (to 1 decimal place): [tex]\(\theta \approx 139.7^\circ\)[/tex]
- In radian measure (to at least 4 decimal places): [tex]\(\theta \approx 2.4379\)[/tex] radians