Question

Find the value of following expression
(a)tan 15° + tan 75°
(a)tan 15°+tan 195°

Answer 1

Answer:

tan 15°= (√3-1)/2√2 and tan 75° = (√3+1)/2√2. tan(195°)=tan(180°+15°) =

tan 180°+tan 15°

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1-tan(180°)tan(15°)

= 0+tan 15°/1-(0)tan 15° = tan 15°.

(a) tan 15°+tan 75° =>(√3+1+√3-1)/2√2 =>2√3/2√2 => √3/√2.

(b) tan 15° + tan 195° = 2tan 15° = 2(√3-1)/2√2 = (√3-1)/√2. Hope it helps you.