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If sinA=3/5, where 0^0ltAlt90^0 , then f...

If `sinA=3/5`, where `0^0ltAlt90^0` , then find the values of `sin2A , cos2A ,tan2A` and `sin4A`

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`sinA = 3/5`
As `A` lies in first quadrant, each trigonometric function will be positive.
`:. cosA = sqrt(1-(3/5)^2) = 4/5`
`tanA = sinA/cosA = 3/4`
`:. sin2A = 2sinAcosA = 2(3/5)(4/5) = 24/25`
`cos2A = 2cos^2A - 1 = 2(4/5)^2 - 1 = 32/25 -1 = 7/25`
`tan2A = (sin2A)/(cos2A) = 24/7`
`sin4A = 2sin2Acos2A = 2(24/25)(7/25) = 336/625.`
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