# Find the exact value of each expression. (tan)(17pi)/12

Find the exact value of each expression.
$$\displaystyle{\left({\tan}\right)}\frac{{{17}\pi}}{{12}}$$

• Questions are typically answered in as fast as 30 minutes

### Plainmath recommends

• Get a detailed answer even on the hardest topics.
• Ask an expert for a step-by-step guidance to learn to do it yourself.

Clara Reese
1. Split up the argument of the trigonometric function and then use the Sum formula for the Tangent function, $$\displaystyle{\tan{{\left({u}+{v}\right)}}}=\frac{{{\tan{{\left({u}\right)}}}+{\tan{{\left({v}\right)}}}}}{{{1}-{\tan{{\left({u}\right)}}}{\tan{{\left({v}\right)}}}}}$$ , to find the value of given expression.
2. $$\displaystyle{\tan{{\left(\frac{{{17}\pi}}{{12}}\right)}}}={\tan{{\left(\frac{{{9}\pi}}{{12}}+\frac{{{8}\pi}}{{12}}\right)}}}$$
$$\displaystyle={\tan{{\left(\frac{{{3}\pi}}{{4}}+\frac{{{2}\pi}}{{3}}\right)}}}$$
$$\displaystyle=\frac{{{\tan{{\left(\frac{{{3}\pi}}{{4}}\right)}}}+{\tan{{\left(\frac{{{2}\pi}}{{3}}\right)}}}}}{{{1}-{\left({\tan{{\left(\frac{{{3}\pi}}{{4}}\right)}}}{\tan{{\left(\frac{{{2}\pi}}{{3}}\right)}}}\right.}}}$$
$$\displaystyle=\frac{{-{1}+{\left(-\sqrt{{3}}\right)}}}{{{1}-{\left(-{1}\right)}\cdot{\left(-\sqrt{{3}}\right)}}}$$
$$\displaystyle=\frac{{-{1}-\sqrt{{3}}}}{{{1}-\sqrt{{3}}}}$$
$$\displaystyle=\frac{{{\left(-{1}-\sqrt{{3}}\right)}{\left({1}+\sqrt{{3}}\right)}}}{{{\left({1}-\sqrt{{3}}\right)}{\left({1}+\sqrt{{3}}\right)}}}$$
$$\displaystyle=\frac{{-{1}-{2}\sqrt{{3}}-{3}}}{{{1}-{3}}}$$
$$\displaystyle=\frac{{{4}-{2}\sqrt{{3}}}}{{-{{2}}}}$$
$$\displaystyle={2}+\sqrt{{3}}$$
Result : $$\displaystyle{\tan{{\left(\frac{{{17}\pi}}{{12}}\right)}}}={2}+\sqrt{{3}}$$
###### Have a similar question?

• Questions are typically answered in as fast as 30 minutes