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shtirl [24]
3 years ago
10

Find the exact value of tan 15 degrees

Mathematics
1 answer:
pentagon [3]3 years ago
4 0
<span>tan(15) = 
sin(15) / cos(15) = 
sin(45 - 30) / cos(45 - 30) = 
[ sin(45)cos(30) - sin(30)cos(45) ] / [ cos(45)cos(30) + sin(45)sin(30)] 

Since sin(45) = cos(45) = √2/2, you can just factor that out from the top and bottom 
[ cos(30) - sin(30) ] / [ cos(30) + sin(30)] 
[ √3/2 - 1/2 ] / [ √3/2 + 1/2] 
(√3 - 1) / (√3 + 1) 
(√3 - 1)^2 / (√3+1)(√3 - 1) 
(√3 - 1)^2 / (3 - 1) 
(3 - 2√3 +1) / 2 
2 - √3 

There's also a formula for tan(a-b), but I couldn't remember it off hand.</span>
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Answer:

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    8.26                      1.68          13.8768          68. 2276          2.8224

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       1.76                       0                0                   3.0976                 0

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-----------------------------------------------------------------------------------------------------------

       ∑x_{i} =                 ∑y_{i} =              ∑x_{i} y_{i}=               ∑x_{i}^{2} y_{i}^{2}=             ∑y_{i} ^{2}=      

      71.98                   62.17         1061.479            1166.8046      1079.8017  

-------------------------------------------------------------------------------------------------------------

Correlation Coefficient or Pearson Correlation is given by:  

the rest calculation is in the attached image

3 0
3 years ago
1. Sam knows that his MP3 player has 40% of its battery life left and that the battery
Korolek [52]

Complete question :

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6 0
3 years ago
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Answer:

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8 0
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