Precal Blog

Eric here to summarize our third hour class period from wednesday.

For the first portion of class, we reviewed the difference between the reciporical and the inverse of cosine.

Reciporical:

1/cos? = sc? = cos?^-1

Inverse:

cos^-1 = cos^-1(u/r) =?

The second part of class included applying what we have learned in the past years to what we have learned in the past days.  Last year we learned how to solve algebra trigonometrey problems.  What we have learned so far in the last few class periods have helped us better understand the main concepts of these problems.

We did two problems of this type:

1.

This simple problem involved using tangent to solve for the height of a flagpole.  The angle of elevation and the length of the shadow casted was given in the problem.  The knowledge that tangent is opposite/adgacent allowed us to solve this problem.  I multiplied the tan(36) by 11.6 to find the length of the flagpole.  The final answer was 8.43 m.

2.

In this problem we were given two side lengths and we had to find the measure of the angle.  We still set up the problem the same way, but we must use the inverse of tangent.  The work and solution to this problem was provided by Taylor.

That concluded the class period.  The scribe for monday November 2nd is Jake Streim!