MHB Determine the unknown angle (using the sine law)

  • Thread starter Thread starter eleventhxhour
  • Start date Start date
  • Tags Tags
    Angle Law Sine
AI Thread Summary
Using the sine law, the calculated angle Θ is 68 degrees, with a second possibility of 112 degrees. However, the textbook indicates the answers should be Θ = 68 degrees and Θ = 23 degrees. The discussion confirms that the initial calculations were correct, suggesting a misunderstanding of the sine law's application. The discrepancy likely arises from the need to consider the sine function's properties and the range of possible angles. The conversation concludes with agreement on the correctness of the calculations.
eleventhxhour
Messages
73
Reaction score
0
View attachment 2479

So using the sine law, I found that Θ = 68 degrees. And the I found that the other possibility of Θ would be 112 degrees (180 - 68 = 112). However, the textbook says that the answers are Θ = 68 and Θ = 23. What did I do wrong?

Thanks.
 

Attachments

  • 4b.png
    4b.png
    3 KB · Views: 91
Mathematics news on Phys.org
I agree with your result, rounded to the nearest degree. You did everything correctly. :D
 
MarkFL said:
I agree with your result, rounded to the nearest degree. You did everything correctly. :D

Alright, thanks! (:
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Back
Top