{"id":6893,"date":"2021-10-21T22:11:15","date_gmt":"2021-10-21T16:41:15","guid":{"rendered":"https:\/\/mathemerize.com\/?p=6893"},"modified":"2021-10-25T09:56:32","modified_gmt":"2021-10-25T04:26:32","slug":"solve-cos3x-sin2x-sin4x-0","status":"publish","type":"post","link":"https:\/\/mathemerize.com\/solve-cos3x-sin2x-sin4x-0\/","title":{"rendered":"Solve : cos3x + sin2x – sin4x = 0"},"content":{"rendered":"
we have, cos3x + (sin2x – sin4x) = 0<\/p>\n
= cos3x – 2sinx.cos3x = 0<\/p>\n
\\(\\implies\\)\u00a0 (cos3x)(1 – 2sinx) = 0<\/p>\n
\\(\\implies\\)\u00a0 cos3x = 0\u00a0 or\u00a0 sinx = \\(1\\over 2\\)<\/p>\n
\\(\\implies\\)\u00a0 cos3x = 0 = cos\\(\\pi\\over 2\\)\u00a0 or\u00a0 sinx = \\(1\\over 2\\) = sin\\(\\pi\\over 6\\)<\/p>\n
\\(\\implies\\)\u00a0 3x = 2n\\(\\pi\\) \\(\\pm\\) \\(\\pi\\over 2\\)\u00a0 or\u00a0 x = m\\(\\pi\\) + \\({(-1)}^m\\)\\(\\pi\\over 6\\)<\/p>\n
\\(\\implies\\)\u00a0 x = \\(2n\\pi\\over 3\\) \\(\\pm\\) \\(\\pi\\over 6\\)\u00a0 or\u00a0 x = m\\(\\pi\\) + \\({(-1)}^m\\)\\(\\pi\\over 6\\); (n, m \\(\\in\\) I)<\/p>\n
If \\({1\\over 6}sin\\theta\\), \\(cos\\theta\\) and \\(tan\\theta\\) are in G.P. then the general solution for \\(\\theta\\) is<\/a><\/p>\n Find the number of solutions of tanx + secx = 2cosx in [0, \\(2\\pi\\)].<\/a><\/p>\n Solve : 6 \u2013 10cosx = 3\\(sin^2x\\)<\/a><\/p>\n