Question 1188581: Calculate:
A) Tan^2 225degrees-sin 60 degrees cos 30 degrees ( don't understand what the Tan to the exponent 2 means)
B) cos 45 degrees sin 225 degrees+ cos 330 degrees
Found 2 solutions by Alan3354, ikleyn:
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! Calculate:
A) Tan^2 225degrees-sin 60 degrees cos 30 degrees ( don't understand what the Tan to the exponent 2 means)
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It's the tan(225) squared
tan(225) = 1 ---> tan^2(225) = 1
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Use parentheses
A) Tan^2(225)-sin(60)*cos(30) = 
= 1 - 3/4 = 1/4
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B) cos(45)*sin(225)+cos(330 = cos(45)*(-sin(45)) + cos(30)
Answer by ikleyn(52879)  (Show Source):
You can put this solution on YOUR website! .
tan(225°) = 1
tan^2(225°) = 1^2 = 1
sin(60°) = 
cos(30°) = .
Having these my hints, you do the rest.
The angles 0°, 30°, 45°, 60°, 90°, 120°, 135°, 150°, 180°, 210°, 225°, 240°, 270°, 300°, 315°, 330°, 360°
are special angles, and EVERY student studying Trigonometry MUST know the values of all trigonometry functions at these angles
precisely in the same way as more young students know the multiplication table.
If you do not know it, it means that YOU ARE in WRONG CLASS.
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You can find these tables in the Internet, see the links
https://www.mathwords.com/t/trig_values_of_special_angles.htm
https://mathvox.com/table-of-the-trig-functions-of-special-angles/
https://www.livingston.org/cms/lib9/NJ01000562/Centricity/Domain/742/calc/Trig%20functions%20chart%20-%20answers.pdf
especially the last link.
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