Question

Sin 30° - cos 30°/sin 60°?

Answer 1

`cos 30^circ = sin 60^circ` because they're complementary angles, so this is

`sin 30^circ - {cos 30^circ} /{ sin 60^circ} = sin 30^circ - 1 = 1/2 - 1=-1/2`

Explanation:

Yet another 30/60/90 question. Get new a triangle people!

I'll assume this is

`\sin 30^circ - cos 30^circ /sin 60^circ`

I'm never really sure because many students forget to add parentheses around the numerator and denominator when typing in a question with a big fraction bar.

We could of course do this one "brute force" by substituting in the trig values we know so well:

`\sin 30^circ - cos 30^circ /{sin 60^circ} = 1/2 - {\sqrt{3}/2}/{\sqrt{3}/2 } = -1/2`