Hello : 
13π/4  = (16-3)π/4
            = 16π/4 -3π/4
  13π/4  = -3π/4 +4π   
 tan( 13π/4) = tan ( -3π/4)= -  tan ( 3π/4)  =- tan( π - π/4) = - tan(- π/4)
tan( 13π/4) = -(-tan(π/4)) =tan(π/4)=1
        
                    
             
        
        
        
Answer:
the rational numbers that doesn’t have a reciprocal are [math]0 [/math] (which can also be expressed as [math]\frac {0} {x}, x \neq 0 [/math] ), and any number of the form [math]\frac {x} {0} [/math].
Step-by-step explanation:
 
        
             
        
        
        
Answer:8.6
Step-by-step explanation:
The easiest way to do this is for you to subtract all the sides from the total perimeter since the perimeter is all of the sides added and your remainder is your answer 
Hope this helps
 
        
                    
             
        
        
        
Lol I’m tempted to steal these but I’m lazy