{"id":8019,"date":"2021-11-13T14:59:50","date_gmt":"2021-11-13T09:29:50","guid":{"rendered":"https:\/\/mathemerize.com\/?p=8019"},"modified":"2021-11-13T16:24:06","modified_gmt":"2021-11-13T10:54:06","slug":"prove-that-the-function-fx-x3-3x2-3x-100-is-increasing-on-r","status":"publish","type":"post","link":"https:\/\/mathemerize.com\/prove-that-the-function-fx-x3-3x2-3x-100-is-increasing-on-r\/","title":{"rendered":"Prove that the function f(x) = \\(x^3 – 3x^2 + 3x – 100\\) is increasing on R"},"content":{"rendered":"
We have, f(x) = \\(x^3 – 3x^2 + 3x – 100\\)<\/p>\n
\\(\\implies\\)\u00a0 f'(x) = \\(3x^2 – 6x + 3\\) = \\(3(x – 1)^2\\)<\/p>\n
Now, x \\(\\in\\) R \\(\\implies\\)\u00a0 \\((x – 1)^2\\)\u00a0 \\(\\ge\\)\u00a0 0\u00a0 \\(\\implies\\)\u00a0 f'(x)\u00a0 \\(\\ge\\) 0.<\/p>\n
Thus, f'(x) \\(\\ge\\) 0 for all x \\(\\in\\) R.<\/p>\n
Hence, f(x) is increasing on R.<\/p>\n
Prove that \\(f(\\theta)\\) = \\({4sin \\theta\\over 2 + cos\\theta} \u2013 \\theta\\) is an increasing function of \\(\\theta\\) in \\([0, {\\pi\\over 2}]\\).<\/a><\/p>\n Separate \\([0, {\\pi\\over 2}]\\) into subintervals in which f(x) = sin 3x is increasing or decreasing.<\/a><\/p>\n Find the point of inflection for f(x) = \\(x^4\\over 12\\) \u2013 \\(5x^3\\over 6\\) + \\(3x^2\\) + 7.<\/a><\/p>\n Find the point of inflection for the curve y = \\(x^3 \u2013 6x^2 + 12x + 5\\).<\/a><\/p>\n