Mối liên hệ với các mô hình toán học trong khoa học xã hội

Apr 24, 2017 ... A more-general version of this question: "How can we sum up sin and cos series when the angles are in arithmetic progression?" (cos(x) + isin(x)). 3. = cos(3x) + isin(3x). By comparing coefficients, we have cos(3x) = cos. 3. (x) − 3 sin. 2. (x) cos(x) and sin(3x) = 3 sin(x) cos. 2. = !e2X sin 3x + ~e2X cos 3x - if e2x cos 3x dx. 3. 9. 9. => (1 + ~) f e2x cos 3x dx = ~e2X sin 3x + ~e2X cos 3x f e2x. => e2x cos 3x dx = 13(3 sin 3x + 2 cos 3x) ... Yp = -9 A Cos 3x-9B Sin 3x. Plug into ODE: (-9A (os 3x-98 Sin 3x)+4(-3A Sin 3x + 3B Cos3x). + 4 CA Cos 3x + B Sin 3x). = [-5A ]. T-5. +12B Cos 3x + -12A-5B ... period y=sin(x)*cos(3x). Natural Language; Math Input. Have a question about using Wolfram|Alpha?Contact Pro Premium Expert Support ». Oct 25, 2017 ... How to integrate cos^3 x. ... (cos(x) In (wing)) dx. 1'(x)=-mi(3x) - 3. In (mix) + cos(3x). (3x).3. fox. +63(3X) cos x. Sari X. (6713x)) co>x. SmiX. (s) (3X). (smi x. 3 . (sm (3x)) In (smix) ... If x is an acute angle and sin ( x + 28 ° ) = cos ( 3 x − 78 ° ) then the angle is · The equation b cos ⁡ x 2 cos 2 x − 1 = b + sin ⁡ x cos 2 ⁡ x − 3 sin ⁡ x ... Cos3x is a triple angle identity in trigonometry. It is a specific case of compound angles identity of the cosine function. ∫ cos (3x + 5) dx. Solution: Let u = 3x + 5, then du/dx = 3 and dx = du/3 ... −1/3 cos (3x − 1) + C. Note: The final result can also be obtained using ...