来自代少升的问题
若sin(x+5π/12)的平方-sin(x-5π/12的平方)=-根号3/4且x∈(3π/4,π),求tanx
若sin(x+5π/12)的平方-sin(x-5π/12的平方)=-根号3/4且x∈(3π/4,π),求tanx
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2020-06-24 18:16
若sin(x+5π/12)的平方-sin(x-5π/12的平方)=-根号3/4且x∈(3π/4,π),求tanx
若sin(x+5π/12)的平方-sin(x-5π/12的平方)=-根号3/4且x∈(3π/4,π),求tanx
sin^2(x+5π/12)-sin^2(x-5π/12)=-√3/4{sin(x+5π/12)+sin(x-5π/12)}{sin(x+5π/12)-sin(x-5π/12)}=-√3/42sin[(x+5π/12+x-5π/12)/2]cos[(x+5π/12-x+5π/12)/2]*2cos[(x+5π/12+x-5π/12)/...