Understanding Trig Function Questions in the Range of Pi to 2Pi

[DethRose]

Im having some problems with some trig function question...im not really understanding what they are asking with these type of questions?

help please

determine the larger angle a in the range pie<a<2pie

sec A = 1.2048

answer a= (in radians)

the answer is 5.6915 rads

 

[courtrigrad]

ok so the question is that we want to determine the larger angle $$\alpha$$ in the range $$\pi < \alpha < 2\pi$$

Now $$\sec x = \frac{1}{\cos x}$$ See if you can go from here.

 

[faust9]

First, start off by writing secant as a cosine function:

$$\frac{1}{\cos A}=1.2048$$

Now, solve the function for A. Remember, $\arccos A$ is only defined from 0 to $\pi$ so you have to find a corresponding angle between $\pi$ and $2\pi$

good luck.

 

[DethRose]

yea but how do i put it in radians?

 

[Doc Al]

This question would make more sense if asked about the range from 0 to $2\pi$, since there would be two angles with sec = 1.2048. But there's only one in the range of $\pi$ to $2\pi$, so the question doesn't make that much sense.