设方程x²+3[sqrt(3)]x+4=0的实数根为x1,x2,α=arctanx1,β=arctanx2,求α+β
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设方程x²+3[sqrt(3)]x+4=0的实数根为x1,x2,α=arctanx1,β=arctanx2,求α+β
设方程x²+3[sqrt(3)]x+4=0的实数根为x1,x2,α=arctanx1,β=arctanx2,求α+β
设方程x²+3[sqrt(3)]x+4=0的实数根为x1,x2,α=arctanx1,β=arctanx2,求α+β
tan(alfh+beta)=(tan(alfh)+tan(beta))/1-tan(alfh).tan(beta)
But
tan(alth)=x1
tan(beta)=x2
So
tan(alfh+beta)=sum of roots/1-product of roots
tan(alfh+beta)=(-3.sqrt(3))/1-4
tan(alfh+beta)=sqrt(3)
tan(alfh+beta)=tan(60°)
alfh+beta=60°
计算机告诉我是-120
楼上的回答,很好。。。嘿嘿