An angle is given to one significant figure as 7 degrees

AI Thread Summary
The angle of 7 degrees corresponds to a range of 6.5 to 7.5 degrees, prompting the need to find the cosine values for these limits. The cosine of 7.5 degrees is calculated, as is the cosine of 6.5 degrees, to determine the range of possible cosine values. The discussion highlights that the result may have more significant figures than the input data, leading to questions about how to appropriately report the cosine range. Participants are encouraged to analyze the cosine values and consider how to represent them accurately. Ultimately, the focus is on understanding the implications of significant figures in trigonometric calculations.
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An angle is given to one significant figure as 7 degrees, meaning that's its value is between 6.5 degrees and 7.5 degrees. Find the corresponding range of possible values of the cosine of the angle. Is this a case in which there are more significant figures in the result than in the input data?

I know the answer to the last question is yes. When I type in cos(7) I get 0.9925461516. Would I round this up to 1 degree, thus its range of values is between 0.5 degrees and 1.5 degrees?

thanks
 
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The angle is between 6.5 and 7.5 degrees, but you aren't sure. It's asking you to find what range the cosine of that angle lies in.
 
The largest the angle can be is 7.5 degrees. What is the cosine of 7.5 degrees?

The smallest the angle can be is 6.5 degrees. What is the cosine of 6.5 degrees?

Now, what do YOU think the possible range for cosine is? You may notice that some of the digits in the two answers are the same. What would be a good way of reporting a single number to represent that range?
 
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