Question

What signs are cos( – 80°) and tan( - 80°)? cos( - 80°) < 0 and tan( - 80°) > 0 . O. They are both negative. cos( - 80°) > 0 and tan( - 80°) < 0 - o. They are both positive.

Answer 1

The angle -80° is located at the IV quadrant:

In this quadrant, the x-coordinates are positive, which means, cosine is positive, and the y-coordinates are negative, then sine is negative.

Also tangent is:

`\tan \theta=(\sin \theta)/(\cos \theta)=(-)/(+)`

Thus, by the law of signs, the tangent is negative in the IV quadrant.

Therefore, the answer is:

cos(-80°)>0 and tan(-80°)<0