9 is a square number because when you use the dot diagram, 9 dots form a square. They are in a 3 by 3 square.
I attached how to show this.
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Hope this helps.
 
        
             
        
        
        
Answer:
The exact values of the tangent, secant and cosine of angle theta are, respectively:



Step-by-step explanation:
The components of the unit vector are  and
 and  . Since
. Since  , then
, then  and
 and  . By Trigonometry, tangent and secant can be calculated by the following expressions:
. By Trigonometry, tangent and secant can be calculated by the following expressions:


Now, the exact values of the tangent, secant and cosine of angle theta are, respectively:



 
        
             
        
        
        
Answer:
i think it's c but I'm rly not sure on this one...