Các bài toán về ứng dụng của tích phân trong hình học và vật lý

Apr 4, 2020 ... cos(x) cos(2x) cos(3x)···cos(nx)dx = 0? Problem 3. Suppose that k and n are positive integers, a1,a2,...,ak ∈ {1,2,...,n} and b1,b2 ... ... cos(3x)°. What is the value of x? 1) 10. 2) 15. 3) 20. 4) 25. 19 If sin(2x + 7)° = cos(4x − 7)°, what is the value of x? 1) 7. 2) 15. 3) 21. 4) 30. 20 If sin(3x ... Jul 26, 2020 ... Comments Section ... Or using u = ei x = cos(x)+i*sin(x), you're expressing cos(3x) = (u3+1/u3)/2 in terms of powers of cos(x) = (u+1/u)/2, ... Feb 28, 2013 ... 3 Answers 3 ... You have cosxcosy=12(cos(x+y)+cos(x−y)). Hence cos(2x)cos(3x)=12(cos(5x)+cosx). This should be straightforward to integrate. ... Or ... Refine=1−29​x2+827​x4−8081​x6+4480729​x8+… Enter ... The solution to the differential equation can be determined by multiplying both sides of the equation by an integrating factor. Free math problem solver answers your algebra, geometry, trigonometry, calculus, and statistics homework questions with step-by-step explanations, ... esin 3x cos 3x dx = 1. 3 esin 3x + C. 53. Z e7x e7x + 5 dx = 1. 7 ln(e7x + 5) + C. 54. Z tan x dx = Z sin x cos x dx. Using the substitution u = cos x, we see ... period y=sin(x)*cos(3x). Natural Language; Math Input. Have a question about using Wolfram|Alpha?Contact Pro Premium Expert Support ». Nov 21, 2023 ... ... e − 2 x cos ⁡ 3 x {\displaystyle \displaystyle -6M{{e}^{-2x}}\sin 3x+(-8M+6N){{e}^{-2x}}\cos 3x-10Mx{{e}^{-2x}}\cos 3x=2{{e}^{-2x}}\cos 3x}.