# Thread: TRIG QUESTION :) ( yes another )

1. ## TRIG QUESTION :) ( yes another )

Determine θ in decimal degrees, 0° θ 90°. Round results to an appropriate number of significant digits.

sec θ = 1.5

answer = 48 degrees

how do i get to this answer?

2. Originally Posted by HelpMePleaseFriend
Determine θ in decimal degrees, 0° θ 90°. Round results to an appropriate number of significant digits.

sec θ = 1.5

answer = 48 degrees

how do i get to this answer?
recall: $\sec \theta = \frac 1{\cos \theta}$

so, $\sec \theta = 1.5$

$\Rightarrow \frac 1{\cos \theta} = 1.5$

$\Rightarrow \cos \theta = \frac 1{1.5}$

$\Rightarrow \theta = \cos^{-1} \left( \frac 1{1.5} \right)$

now plug that into your calculator (remember to put it in degrees mode this time )