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lr1265

The exact value of tan(5pi/12) is equal to 2 + sqrt(3)

Answer:

The exact value of \(\tan (\frac{5\pi}{12})\) is \(2+\sqrt{3}\)

Step-by-step explanation:

We need to calculate the exact value of \(\tan (\frac{5\pi}{12})\)

Since, \(\tan \frac{x}{2} = \frac{1- \cos x}{\sin x}\)

Put \(x= \frac{5 \pi}{6}\) in above

\(\tan (\frac{5\pi}{12}) = \frac{1- \cos \frac{5\pi}{6}}{\sin \frac{5\pi}{6}}\)

Since,

\(\cos \frac{5\pi}{6}}=\frac{-\sqrt{3}}{2}\)

\(\sin \frac{5\pi}{6}}=\frac{1}{2}\)

\(\tan (\frac{5 \pi }{12}) = \frac{1+\frac{\sqrt{3}}{2}}{\frac{1}{2}}\)

\(\tan (\frac{5 \pi }{12}) = \frac{\frac{2+\sqrt{3}}{2}}{\frac{1}{2}}\)

\(\tan (\frac{5 \pi }{12}) = 2+\sqrt{3}\)

Therefore, the exact value of \(\tan (\frac{5\pi}{12})\) is \(2+\sqrt{3}\)