How do you simplify $(sin80°-sin10°) / (sin80°+ sin10°)$ ?

Question

5896 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-11-02T15:24:30

$(sin 80^@ - sin 10^@)/(sin 80^@ + sin 10^@) = tan 35^@$

$sin a ± sin b = 2 sin ((a±b)/2) cos ((a∓b)/2)$
$tan A = sin A/cos A$

$(sin 80^@ - sin 10^@)/(sin 80^@ + sin 10^@) = sin 35^@ cos 45^@/(sin 45^@cos 35^@) = tan 35^@/(tan 45^@) = tan 35^@$

How do you simplify (sin80°-sin10°) / (sin80°+ sin10°) (sin80°-sin10°) / (sin80°+ sin10°)?