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Help plsssss!!!! i dont get it

Help plsssss!!!! i dont get it-example-1

1 Answer

7 votes

Answer:

sin2θ =
(1320)/(3721)

Explanation:

Given

sinθ =
(11)/(61) =
(opposite)/(hypotenuse)

This is a right triangle with legs 11 and x ( adjacent ) and hypotenuse 61

Using Pythagoras' identity in the right triangle to find x

x² + 11² = 61²

x² + 121 = 3721 ( subtract 121 from both sides )

x² = 3600 ( take the square root of both sides )

x =
√(3600) = 60

Then cosθ =
(adjacent)/(hypotenuse) =
(60)/(61)

Using the identity

sin2θ = 2sinθcosθ , then

sin2θ = 2 ×
(11)/(61) ×
(60)/(61) =
(1320)/(3721)

User Sean McKenna
by
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