Bài toán về thể tích vật thể tròn xoay

sen3(x - a) cos 3a + cos 3(x - a)sen3a - sen3a. x-a. =cos 3asen3(x - a) x-a+ ... x(cos 3x + 1) =0. Es decir, lim. '→a senx - sena. x-a =3 cos 3a. b ... Sep 2, 2018 ... Cos^3(x)=(cos3x+3cosx) ÷4. Upvote ·. 9929. 91. As x approaches negative infinity, the value of cos ⁡ 3 x will oscillate between -1 and 1. However, the denominator, x , will become increasingly negative. This ... Expression 1: "f" left parenthesis, "x" , right parenthesis equals cosine left parenthesis, 6 "x" , right parenthesis Has graph. To audio trace, press ALT+T ... Let x = cos 200. Then we get, from the formula for cos 3x,. 4x3-3x=4 cos3 20?-3 cos 200 =cos 3(200)= . .. 8x3=6x+1. We now have cos 200 cos 400 cos 800. =x(2x2 ... 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 + α cos (3x/4)). - 8 (cos (x/2) + a cos (x/4))]/α:2. - -^-[1 - cosx + 2(1 ... Similarly, 1 - cos (3x/4)τ/cos (x/2) ^ 1 - (cos (5a/4) + cos (a/4))/2 ... ... 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 ... 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 ... Express each function as a trigonometric function of x. See Example 5.cos 3x.