Use the pythagorean identity to find cos Θ.
sin² Θ + cos² Θ = 1
(¼)² + cos² Θ = 1
cos Θ = ±(√15)/4
<span>Now use the half angle identity
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This is why you need to know the quadrant. If Θ is in Q1, then cos Θ is (√15)/4. If Θ is in Q2, then cos Θ = -(√15)/4.
Also, s<span>ince Θ is in either Q1 or Q2, Θ/2 must be in Q1, and cos (Θ/2) is positive</span>
For Θ in Q1:
For Θ in Q2:
38,000 - 20,000 = 18,000
3% of 18,000 is
0.03 * 18,000 = $540
16n+18 Is The Answer
Hope This Helps
For this problem, you need to create a proportion.
40 inches/12 minutes=100 inches/x
Let x be the number of minutes it takes to weave 100 inches
Solve
40x=1200
x=30 minutes
No 912 inches is wayyy bigger