If cos(Ɵ)=7/8 andƟ is in the 1st quadrant, then what is sin(Ɵ) ?
回答 (3)
square root of fifteen over eight.
Do a simple sketch with theta in Quad 1 and cos theta = 7/8 i.e. Adj = 7, hypot.= 8 so Opp = sqrt (8^2 - 7^2) = sqrt64 - 49 = sqrt 15, so sin theta = Opp/Hypot = sqrt(15)/8
參考: Retired Maths Teacher
收錄日期: 2021-04-30 23:37:29
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