Question 926575
Find the exact values
1. csc240°
reference angle of 240-180=60&#730; resides in quadrant III where cos<0,sin<0
csc240&#730;=1/sin240&#730;=1/sin60&#730;=-1/(&#8730;3/2)=-2/&#8730;3=-2&#8730;3/3
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2. cos270°=0
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3. cos 3&#960;/4
reference angle of &#960;-3&#960;/4=&#960;/4 resides in quadrant II where cos<0,sin>0
cos(3&#960;/4)=cos(&#960;/4)=-&#8730;2/2
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4.cot 3&#960;/2=cos(3&#960;/2)/sin(3&#960;/2)=0/-1=0