# Trig

posted by Paige

tan 75 (show all work please)

1. Reiny

Using tan(A+B) = (tanA + tanB)/(1-tanAtanB)

tan75
= tan(45+30)
= (tan45+tan30)/(1-tan45tan30)
= (1 + 1/√3)/(1 - (1)(1/√3)
multiply top and bottom by √3
= (√3 + 1)/(√3 - 1)

## Similar Questions

1. ### trig

use sum or difference identities to find the exact value of the trigonometric function: tan 345 please show work, i cant figure out what im doing wrong!
2. ### Trig.

sec^2xcotx-cotx=tanx (1/cos)^2 times (1/tan)-(1/tan)=tan (1/cos^2) times (-2/tan)=tan (-2/cos^2tan)times tan=tan(tan) sq. root of (-2/cos^2)= sq. root of (tan^2) sq. root of (2i)/cos=tan I'm not sure if I did this right. If I didn't, …
3. ### trig

please help me. use trig. identities to find the exact value. tan 25° + tan 5° / 1- tan 25° tan 5°
4. ### trig

please help me. use trig. identities to find the exact value. tan 25° + tan 5° / 1- tan 25° tan 5°
5. ### trig

Given that tan 45=1, use tan(x+y) to show that tan 22.5= /2 - 1. (/is square root sign
6. ### Pre-cal/Trig

(tan/(1+sec)) + ((1+sec)/tan) = 2csc (Show all work please.)
7. ### pre-calc

(1+tan x)^2= 2 tan x+2 please show all work
8. ### Math-Trigonometry

Show that if A, B, and C are the angles of an acute triangle, then tan A + tan B + tan C = tan A tan B tan C. I tried drawing perpendiculars and stuff but it doesn't seem to work?