{"id":9466,"date":"2022-01-14T16:14:47","date_gmt":"2022-01-14T10:44:47","guid":{"rendered":"https:\/\/mathemerize.com\/?p=9466"},"modified":"2022-01-14T16:25:27","modified_gmt":"2022-01-14T10:55:27","slug":"general-solution-of-the-equation-of-form-a-costheta-b-sin-theta-c","status":"publish","type":"post","link":"https:\/\/mathemerize.com\/general-solution-of-the-equation-of-form-a-costheta-b-sin-theta-c\/","title":{"rendered":"General Solution of the Equation of form \\(a cos\\theta\\) + \\(b sin \\theta\\) = c"},"content":{"rendered":"
General Solution of the equation \\(a cos\\theta\\) + \\(b sin \\theta\\) = c,<\/h2>\n
where a, b, c \\(\\in\\) R such that | c | \\(\\le\\) \\(\\sqrt{a^2 + b^2}\\).<\/p>\n
To solve this type of equations, we first reduce them in the form \\(cos \\theta\\) = \\(cos \\alpha\\),\u00a0 or\u00a0 \\(sin \\theta\\) = \\(sin \\alpha\\).<\/p>\n
The following algorithm provides the method of solution.<\/p>\n
Algorithm :<\/strong><\/p>\n
Step 1 : Obtain the equation \\(a cos\\theta\\) + \\(b sin \\theta\\) = c<\/p>\n
Step 2 : Put a = \\(r cos\\alpha\\)\u00a0 and\u00a0 b = \\(r sin \\alpha\\) ,\u00a0 where\u00a0 r = \\(\\sqrt{a^2 + b^2}\\) and \\(tan \\alpha\\) = \\(b\\over a\\)\u00a0 i.e. \\(\\alpha\\) = \\(tan^{-1} (b\/a)\\).<\/p>\n
Step 3 : Using the substitution in step 2, the equation reduces to \\(r cos(\\theta – \\alpha)\\) = c \\(\\implies\\) \\(cos(\\theta – \\alpha)\\) = \\(c\\over r\\) = \\(cos \\beta\\) (say).<\/p>\n