Earth takes 24 hours to complete one rotation. It rotates at an average speed of 1670 km/hour. Calculate the earth's circumference at the equator based on its rotational speed. Show your work (hint: distance = rate x time)

Which sum or difference identity would you use to verify that cos (180° - ∅) = -cos ∅? a. sin (α -β) = sin α cos β – cos α sin β b. cos (α -β) = cos α cos β – sin α sin β c. cos (α -β) = cos α cos β + sin α sin β d. sin (α + β) = sin α cos β + cos α sin β

How to solve a simultaneous equation involved with fractions?

If 1/√5+1/√5+1=p+q√r , find the values of p, q and r