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Find exact value of the expression find sin (2theta) , when cos(theta) =4/5 and theta lies in quadrant IV

  • one year ago
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  1. alexjb1007
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    To start with the triangle is a 3,4,5 triangle based on cos theta = 4/5. Secondly the sin (2theta) is equal to 2sin(theta)cos(theta)[double angle identity]. The sin of theta would equal 3/5. So 2(3/5)(4/5) = 24/5.

    • one year ago
  2. kdeedee02
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    thanx for your help

    • one year ago
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