Question

E3 va rog mult dau coroana

Answer 1

Hello, pentru a rezolva aceste exercitii, trebuie sa stim 2 lucruri:
1) Valorile functiilor trigonometrice
2) La cazul c: perioada functiilor.
a) sin 30° = 1/2 
tg 60° = radical(3)
tg 45° = 1 =>
2* 1/2 + 5*radical(3) + 6*2 = 7 + 5*radical(3)
b) cos 60° = 1/2
sin 60° = radical(3)/2
tg 30° = radical(3)/3 =>
1/2 /(1 + radical(3)/2) + 1/(radical(3)/3) = 1/(2 + radical(3)) + 3/radical(3) = [radical(3) + 6 + 3*radical(3)]/[3 + 2*radical(3)] = (6 + 4*radical(3))/(3+2*radical(3)) = 2.
c) sin 390° = sin (360° + 30°) = sin 30° = 1/2
cos 390° = cos (360° + 30°) = cos 30° = radical(3)/2
tg 405° = tg (2*180° + 45°) = tg 45° = 1
sin 405° = sin (360° + 45°) = sin 45° = radical(2)/2
cos 405° = cos (360° + 45°) = cos 45° = radical(2)/2
tg 390° = tg (2*180° + 30°) = tg 30° = radical(3)/3
[1/2 + radical(3)/2 + 1]/[radical(2)/2 + radical(2)/2 + radical(3)/3] = (3 + radical(3))/(2*radical(2) + 2*radical(3)/3) = (9 + 3*radical(3))/(6*radical(2) + 2*radical(3))