Values of Sec

Question

Suppose sin(β) = 1/5. Find the exact simplified value of sec(β) for 0 < β < π/2

How do I find the value of sec in this domain. 

Answer 1

β is in QI or QII (sin β is positive)

By Pythagoras, cos β = ±2√6 / 5, cosine is positive in QI and negative in QII.

sec β = 1 / cos β

 

What are the values of sec β?