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tan75° = 3.7321

Answer:

Value of tan 75° = 3.7317

Step-by-step explanation:

To find its value we use the following formula,

\(tan(a+b)=\frac{tan\,a+tan\,b}{1-tan\,a\:tan\b}\)

we also use value of tan 30° = 1/√3  and tan 45° = 1  and √3 =1.7321

\(tan\,75=tan\,(45+30)=\frac{tan\,45+tan\,30}{1-tan\,45\:tan\,30}\)

               \(=\frac{1+\frac{1}{\sqrt{3}}}{1-1\times\frac{1}{\sqrt{3}}}\)

               \(=\frac{\frac{\sqrt{3}+1}{\sqrt{3}}}{\frac{\sqrt{3}-1}{\sqrt{3}}}\)

               \(=\frac{\sqrt{3}+1}{\sqrt{3}-1}\)

               \(=\frac{1.7321+1}{1.7321-1}\)

               \(=\frac{2.7321}{0.7321}\)

               \(=3.7317\)

Therefore, Value of tan 75° = 3.7317