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1 vote
Need help on this one! 10 points

Need help on this one! 10 points-example-1
User Jktravis
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2 Answers

6 votes
Option 4: 84/2 over 121

sin^2x + cos^2x = 1
sin^2x + (7/11)^2 = 1
sin^2x + 49/121 = 1
sin^2x = 72/121
sinx = square root of 72/121
sinx = (6 root 2) / 11

sin2x = 2sinxcosx
sin2x = 2[(6 root 2)/11] (7/11)
sin2x = (2*6*7*root 2) / (11*11)
sin2x = 84 root 2 / 121 :)
User SeekDaSky
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4.1k points
5 votes
A is the correct form
User Paul Ostrowski
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