Calculating values when combining the tangens and cosinus function

Hello, I'm currently studying for an exam I will have right before semester 2 starts now in August and I could really use some help

The question is basically "Calculate the value of tan(cos^-1(0.5))"

I can't understand why or how I would do this, do I turn cosinus into something using sinus and tangens or where do I begin??

Thank you!

Re: Calculating values when combining the tangens and cosinus function

Quote:

Originally Posted by

**Rask** Hello, I'm currently studying for an exam I will have right before semester 2 starts now in August and I could really use some help

The question is basically "Calculate the value of tan(cos^-1(0.5))"

First, . Ask yourself this...The cosine of what angle is 0.5? (Hint: It's one of the "common" angles.)

-Dan

Re: Calculating values when combining the tangens and cosinus function

Alright, so cos(0.5) = 60deg = 1pi/3

tan(60) = sqrt(3) correct?

and how is this calculated without a calculator, is it possible or do I have to memorize it?

Re: Calculating values when combining the tangens and cosinus function

Quote:

Originally Posted by

**Rask** Alright, so cos(0.5) = 60deg = 1pi/3

tan(60) = sqrt(3) correct?

and how is this calculated without a calculator, is it possible or do I have to memorize it?

It's a good idea to know the sine, cosine, and tangents of 0, pi/6, pi/4, pi/3, pi/2. (0, 30, 45, 60, 90 in degrees.) They come up all the time in Trig.

One correction: cos(0.5) is not 60. You meant that cos(60) = 0.5 Otherwise, yes, you have it right!

-Dan

Re: Calculating values when combining the tangens and cosinus function