8(sinα)^2+6msinα+2m+1=0
8(cosα)^2+6mcosα+2m+1=0
相加得8+6m(sinα+cosα)+4m+2=0
sinα+cosα=√2sin(α+π/4)=-(5+2m)/3m即sin(α+π/4)=-(5+2m)/3√2m
又因α是第三象限角,
即π
8(sinα)^2+6msinα+2m+1=0
8(cosα)^2+6mcosα+2m+1=0
相加得8+6m(sinα+cosα)+4m+2=0
sinα+cosα=√2sin(α+π/4)=-(5+2m)/3m即sin(α+π/4)=-(5+2m)/3√2m
又因α是第三象限角,
即π