## anonymous one year ago @Nnesha - Can you Help?: What is the exact value of tan 75 degrees? Not just answers please, explain how to do it... PLEASE HELP!!!

1. ganeshie8

Hint : $$\large 75 = 30+45$$

2. ganeshie8

look up $$\tan(A+B)$$ formula in ur notes

3. anonymous

ok so with the half angle formula right?

4. anonymous

@ganeshie8

5. anonymous

I get this: tan 75 = tan (150)/2 = 1 - cos(theta)/sin (theta) = 1-(-sqrt(3)/2)/(1/2) = 2 + sqrt (3)

6. anonymous

Looks a little weird but I think its right??

7. Nnesha

i would use this one $\huge\rm tan(\color{reD}{a}+\color{blue}{b})=\frac{ \tan \color{red}{a}+ \tan \color{blue}{b} }{ 1-tan\color{reD}{a}tan\color{blue}{b} }$ sum formula for tan

8. Nnesha

a ,b are two numbers on the unit circle that add up to 75 degree

9. Nnesha

look above 't first comment by ganeshie8 30+45=75 so a=30 b=45

10. anonymous

got it thanks!

11. Nnesha

np