Bruno Pittman
2022-07-01
Answered

To prove that $\mathrm{tan}70=\mathrm{tan}20+2\mathrm{tan}50$

You can still ask an expert for help

asked 2021-08-20

Let P(x, y) be the terminal point on the unit circle determined by t. Then

asked 2022-03-31

m is a positive integer.

asked 2022-07-13

how to find $\mathrm{tan}\left(\frac{x}{2}\right)$ knowing that $\mathrm{cos}\left(x\right)+\mathrm{sin}\left(x\right)=\frac{7}{5}$

asked 2022-05-14

Prove that

$\mathrm{cos}\frac{\pi}{7},\mathrm{cos}\frac{3\pi}{7},\mathrm{cos}\frac{5\pi}{7}$

roots of polynomial $8{x}^{3}-4{x}^{2}-4x+1=0$

$\mathrm{cos}\frac{\pi}{7},\mathrm{cos}\frac{3\pi}{7},\mathrm{cos}\frac{5\pi}{7}$

roots of polynomial $8{x}^{3}-4{x}^{2}-4x+1=0$

asked 2022-07-02

What is the value of the expression $[1+\mathrm{cos}(\frac{\pi}{8})][1+\mathrm{cos}(\frac{3\pi}{8})][1+\mathrm{cos}(\frac{5\pi}{8})][1+\mathrm{cos}(\frac{7\pi}{8})]$?

asked 2022-05-26

How does $\pi -\mathrm{arctan}(\frac{8}{x})-\mathrm{arctan}(\frac{13}{20-x})=\mathrm{arctan}(\frac{x}{8})+\mathrm{arctan}(\frac{20-x}{13})$?

asked 2022-02-26

Solve: