{"id":9325,"date":"2022-01-10T00:13:01","date_gmt":"2022-01-09T18:43:01","guid":{"rendered":"https:\/\/mathemerize.com\/?p=9325"},"modified":"2022-01-16T17:13:36","modified_gmt":"2022-01-16T11:43:36","slug":"what-is-the-formula-of-tan-2a","status":"publish","type":"post","link":"https:\/\/mathemerize.com\/what-is-the-formula-of-tan-2a\/","title":{"rendered":"Tan 2A Formula – Proof and Examples"},"content":{"rendered":"
Here you will learn what is the formula of tan 2A in terms of tan with proof and examples based on it.<\/p>\n
Let’s begin –<\/p>\n
\nThe formula of tan 2A is \\(2 tan A\\over 1 – tan^2 A\\)<\/p>\n<\/blockquote>\n
Proof :<\/strong><\/p>\n
We have,<\/p>\n
tan (A + B) = \\(tan A + tan B\\over 1 – tan A tan B\\)<\/p>\n
Replacing B by A,<\/p>\n
\\(\\implies\\) tan 2A = \\(tan A + tan A\\over 1 – tan A tan A\\)<\/p>\n
\\(\\implies\\) tan 2A = \\(2 tan A\\over 1 – tan^2 A\\)<\/p>\n
We can also write above relation in terms of angle A\/2, just replace A by A\/2, we get<\/p>\n
\ntan 2A = \\(2 tan ({A\\over 2})\\over 1 – tan^2 ({A\\over 2})\\)<\/p>\n<\/blockquote>\n
Example<\/strong><\/span> : Find the value of Tan 120 Degrees ?<\/p>\n
Solution<\/span><\/strong> : We Know that tan 60 = \\(\\sqrt{3}\\).<\/p>\n
By using above formula, tan 2A = \\(2 tan A\\over 1 – tan^2 A\\)<\/p>\n
tan 120 = \\(2 tan 60\\over 1 – tan^2 60\\) = \\(2 \\times \\sqrt{3}\\over 1 – 3\\)<\/p>\n
\\(\\implies\\) tan 120 = \\(-\\sqrt{3}\\)<\/p>\n
Example<\/strong><\/span> : If sin A = \\(3\\over 5\\), where 0 < A < 90 degrees, find the value of tan 2A ?<\/p>\n
Solution<\/span><\/strong> : We have,<\/p>\n
sin A = \\(3\\over 5\\) where 0 < A < 90 degrees<\/p>\n
\\(\\therefore\\) \\(cos^2 A\\) = 1 – \\(sin^2 A\\)<\/p>\n
\\(\\implies\\) cos A = \\(\\sqrt{1 – sin^2 A}\\) = \\(\\sqrt{1 – {9\\over 25}}\\) = \\(4\\over 5\\)<\/p>\n
\\(\\implies\\) tan A = \\(sin A\\over cos A\\) = \\(3\/5\\over 4\/5\\) = \\(3\\over 4\\)<\/p>\n
By using above formula,<\/p>\n
tan 2A = \\(2 tan A\\over 1 – tan^2 A\\) = \\(2 \\times {3\\over 4} \\over 1 – {9\\over 16}\\)<\/p>\n
\\(\\implies\\) tan 2A = \\({6\\over 4}\\over {7\\over 16}\\)<\/p>\n
\\(\\implies\\) tan 2A = \\(24\\over 7\\)<\/p>\n\n\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
Here you will learn what is the formula of tan 2A in terms of tan with proof and examples based on it. Let’s begin – Tan 2A Formula : The formula of tan 2A is \\(2 tan A\\over 1 – tan^2 A\\) Proof : We have, tan (A + B) = \\(tan A + tan …<\/p>\n