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Category: Trigonometry

2sin-17x-3-cos-5x-sin-5x-0-x-

Question Number 144828 by mathlove last updated on 29/Jun/21 $$\mathrm{2sin}\:\mathrm{17}{x}+\sqrt{\mathrm{3}}\:\mathrm{cos}\:\mathrm{5}{x}+\mathrm{sin}\:\mathrm{5}{x}=\mathrm{0} \\ $$$${x}=? \\ $$ Answered by liberty last updated on 30/Jun/21 $$\mathrm{2sin}\:\mathrm{17x}\:+\:\mathrm{2cos}\:\left(\mathrm{5x}−\frac{\pi}{\mathrm{6}}\right)=\mathrm{0} \\ $$$$\Rightarrow\mathrm{cos}\:\left(\mathrm{5x}−\frac{\pi}{\mathrm{6}}\right)=−\mathrm{sin}\:\mathrm{17x} \\…

find-the-least-value-of-such-that-4-sin-x-1-1-sin-x-has-at-least-one-solution-in-0-2-

Question Number 144833 by gsk2684 last updated on 29/Jun/21 $$\mathrm{find}\:\mathrm{the}\:\mathrm{least}\:\mathrm{value}\:\mathrm{of}\:\alpha\:\mathrm{such}\:\mathrm{that}\:\frac{\mathrm{4}}{\mathrm{sin}\:\mathrm{x}}+\frac{\mathrm{1}}{\mathrm{1}−\mathrm{sin}\:\mathrm{x}}=\alpha\: \\ $$$$\mathrm{has}\:\mathrm{at}\:\mathrm{least}\:\mathrm{one}\:\mathrm{solution}\:\mathrm{in}\:\left(\mathrm{0}\:\frac{\Pi}{\mathrm{2}}\right) \\ $$ Answered by liberty last updated on 29/Jun/21 $$\alpha=\mathrm{f}\left(\mathrm{x}\right)=\frac{\mathrm{4}}{\mathrm{sin}\:\mathrm{x}}\:+\:\frac{\mathrm{1}}{\mathrm{1}−\mathrm{sin}\:\mathrm{x}} \\ $$$$\mathrm{let}\:\mathrm{u}=\mathrm{sin}\:\mathrm{x}\:\Rightarrow\mathrm{f}\left(\mathrm{u}\right)=\mathrm{4u}^{−\mathrm{1}} +\left(\mathrm{1}−\mathrm{u}\right)^{−\mathrm{1}}…

A-platform-and-a-building-are-on-the-same-horizontal-plane-The-angle-of-depression-of-the-bottom-C-of-the-building-from-the-top-A-of-the-platform-is-39-The-angle-of-elevation-of-the-top-D-of-the-b

Question Number 13737 by chux last updated on 22/May/17 $$\mathrm{A}\:\mathrm{platform}\:\mathrm{and}\:\mathrm{a}\:\mathrm{building}\:\mathrm{are}\:\mathrm{on} \\ $$$$\mathrm{the}\:\mathrm{same}\:\mathrm{horizontal}\:\mathrm{plane}.\mathrm{The} \\ $$$$\mathrm{angle}\:\mathrm{of}\:\mathrm{depression}\:\mathrm{of}\:\mathrm{the}\:\mathrm{bottom} \\ $$$$\mathrm{C}\:\mathrm{of}\:\mathrm{the}\:\mathrm{building}\:\mathrm{from}\:\mathrm{the}\:\mathrm{top}\:\mathrm{A}\: \\ $$$$\mathrm{of}\:\mathrm{the}\:\mathrm{platform}\:\mathrm{is}\:\mathrm{39}°.\mathrm{The}\:\mathrm{angle}\:\mathrm{of}\: \\ $$$$\mathrm{elevation}\:\mathrm{of}\:\mathrm{the}\:\mathrm{top}\:\mathrm{D}\:\mathrm{of}\:\mathrm{the}\: \\ $$$$\mathrm{building}\:\mathrm{from}\:\mathrm{the}\:\mathrm{top}\:\mathrm{of}\:\mathrm{the}\: \\ $$$$\mathrm{platform}\:\mathrm{is}\:\mathrm{56}°.\mathrm{Given}\:\mathrm{that}\:\mathrm{the}\: \\…

Let-be-an-acute-angle-such-that-the-equation-x-2-4xcos-cot-0-involving-variable-x-has-multiple-roots-Then-the-measure-of-in-radians-is-

Question Number 144800 by imjagoll last updated on 29/Jun/21 $$\mathrm{Let}\:\beta\:\mathrm{be}\:\mathrm{an}\:\mathrm{acute}\:\mathrm{angle}\:\mathrm{such} \\ $$$$\mathrm{that}\:\mathrm{the}\:\mathrm{equation}\:\mathrm{x}^{\mathrm{2}} +\mathrm{4xcos}\:\beta+\mathrm{cot}\:\beta=\mathrm{0} \\ $$$$\mathrm{involving}\:\mathrm{variable}\:\mathrm{x}\:\mathrm{has}\:\mathrm{multiple} \\ $$$$\mathrm{roots}.\:\mathrm{Then}\:\mathrm{the}\:\mathrm{measure}\:\mathrm{of}\:\beta\:\mathrm{in} \\ $$$$\mathrm{radians}\:\mathrm{is}\:\_\_ \\ $$ Answered by liberty last…

Express-sin-5x-as-polynomial-in-terms-of-sin-x-

Question Number 144791 by imjagoll last updated on 29/Jun/21 $$\:\mathrm{Express}\:\mathrm{sin}\:\mathrm{5x}\:\mathrm{as}\:\mathrm{polynomial} \\ $$$$\:\mathrm{in}\:\mathrm{terms}\:\mathrm{of}\:\mathrm{sin}\:\mathrm{x}.\: \\ $$ Answered by liberty last updated on 29/Jun/21 $$\mathrm{by}\:\mathrm{DeMoi}'\mathrm{vre}\:\mathrm{theorem} \\ $$$$\Leftrightarrow\:\mathrm{cos}\:\mathrm{5x}+{i}\mathrm{sin}\:\mathrm{5x}\:=\:\left(\mathrm{cos}\:\mathrm{x}+{i}\mathrm{sin}\:\mathrm{x}\right)^{\mathrm{5}} \\…

Let-x-5pi-12-pi-3-then-the-maximum-value-of-y-tan-x-2pi-3-tan-x-pi-6-cos-x-pi-6-is-

Question Number 144780 by imjagoll last updated on 29/Jun/21 $$\:\mathrm{Let}\:\mathrm{x}\in\left[−\frac{\mathrm{5}\pi}{\mathrm{12}},−\frac{\pi}{\mathrm{3}}\right]\:,\:\mathrm{then}\:\mathrm{the}\: \\ $$$$\:\mathrm{maximum}\:\mathrm{value}\:\mathrm{of}\: \\ $$$$\:\:\mathrm{y}=\mathrm{tan}\:\left(\mathrm{x}+\frac{\mathrm{2}\pi}{\mathrm{3}}\right)−\mathrm{tan}\:\left(\mathrm{x}+\frac{\pi}{\mathrm{6}}\right)+\mathrm{cos}\:\left(\mathrm{x}+\frac{\pi}{\mathrm{6}}\right) \\ $$$$\:\mathrm{is}\: \\ $$ Terms of Service Privacy Policy Contact: info@tinkutara.com