已知角x的终边经过点P(4/5,-3/5) (1)求sinx的值; (2)已知角x的终边经过点P(4/5,-3/5)(1)求sinx的值; (2)求sin(π/2-x)/sin(x+π)×tan(x-π)/cos(3π-x)
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![已知角x的终边经过点P(4/5,-3/5) (1)求sinx的值; (2)已知角x的终边经过点P(4/5,-3/5)(1)求sinx的值; (2)求sin(π/2-x)/sin(x+π)×tan(x-π)/cos(3π-x)](/uploads/image/z/12551823-63-3.jpg?t=%E5%B7%B2%E7%9F%A5%E8%A7%92x%E7%9A%84%E7%BB%88%E8%BE%B9%E7%BB%8F%E8%BF%87%E7%82%B9P%EF%BC%884%2F5%2C-3%2F5%EF%BC%89+%281%29%E6%B1%82sinx%E7%9A%84%E5%80%BC%EF%BC%9B+%282%29%E5%B7%B2%E7%9F%A5%E8%A7%92x%E7%9A%84%E7%BB%88%E8%BE%B9%E7%BB%8F%E8%BF%87%E7%82%B9P%EF%BC%884%2F5%2C-3%2F5%EF%BC%89%281%29%E6%B1%82sinx%E7%9A%84%E5%80%BC%EF%BC%9B+%282%29%E6%B1%82sin%28%CF%80%2F2-x%29%2Fsin%28x%2B%CF%80%29%C3%97tan%28x-%CF%80%29%2Fcos%283%CF%80-x%29)
已知角x的终边经过点P(4/5,-3/5) (1)求sinx的值; (2)已知角x的终边经过点P(4/5,-3/5)(1)求sinx的值; (2)求sin(π/2-x)/sin(x+π)×tan(x-π)/cos(3π-x)
已知角x的终边经过点P(4/5,-3/5) (1)求sinx的值; (2)
已知角x的终边经过点P(4/5,-3/5)
(1)求sinx的值; (2)求sin(π/2-x)/sin(x+π)×tan(x-π)/cos(3π-x)
已知角x的终边经过点P(4/5,-3/5) (1)求sinx的值; (2)已知角x的终边经过点P(4/5,-3/5)(1)求sinx的值; (2)求sin(π/2-x)/sin(x+π)×tan(x-π)/cos(3π-x)
tanx=(-3/5)/(4/5)=-3/4,4sinx=-3cosx,25sin^2x=9,x的终边在第四象限,所以sinx=-3/5
[sin(π/2-x)/sin(x+π)][tan(x-π)/cos(3π-x)]
=[cosx/(-sinx)]{[(-sinx)/(-cosx)]/(-cosx)}
=1/cosx
sinx=-3/4