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Greatest value of Sin4?T + cos4?T is

Greatest value of Sin4Θ + cos4Θ is 

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Ira S. | Bilingual math tutor and much moreBilingual math tutor and much more
5.0 5.0 (248 lesson ratings) (248)
     Actually, the highest value for this sum is when cos 4ø = sin 4ø. cos 45 =s in45, just a fact that you may know. cos 45 =sqrt 2 /2, so sqrt 2 /2 + sqrt 2 /2 = sqrt 2 (approximately 1.414 . So if you're lookig for ø, 4ø = 45 and ø =11.25.


never mind it's (cos ø)^4
The first page reads sin 4ø but the second page reads (sin ø)^4 . If you mean the first case, my answer is correct, but if you mean the second case, Deanna's answer is correct .
2[(√2)/2]4 = 1/2
14 + 04 = 1
So I believe Deanna L.'s answer of 1 was correct
We can take the derivative to check.
4sin3 ΘcosΘ - 4cos3 ΘsinΘ= 0
critical numbers are 0, pi/4, and pi/2
0 and pi/2 give a maximum
pi/4 or 45 degrees is actually the minimum
Deanna L. | Electrical engineering major and music lover with MIT degreeElectrical engineering major and music l...
4.9 4.9 (122 lesson ratings) (122)
The greatest value of sin or cos is one. The catch is when sin is one cosine is zero and vicecovers a. So the answer is one.