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Question
If cosθ = `5/13`, then find sinθ.
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Solution
cosθ = `5/13`
`sin^2θ + cos^2θ = 1`
`sin^2θ + (5/13)^2 = 1`
`sin^2θ = (1 - 25)/169`
`sin^2θ = (169 - 25)/169`
`sin^2θ = 144/169`
sinθ = `sqrt(144/169)`
sinθ = `12/13`
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