Find the value of tan 15 degrees

Home Work Help
1

Find the value of tan 15 degrees

2

Let tan(15°) = tan(45°-30°)

We know that tan(A - B) = (tanA - tanB) /(1 + tan A tan B)

⇒tan(45°-30°) = (tan45°- tan30°)/(1+tan45°tan30°)

= {1- (1/√3)} / {1+(1/√3)}

∴ tan15° = (√3 - 1) / (√3 + 1)