已知tanα=2,求值 {4sin α( π- α)+3cos( π+α )}/ {4cos(3π/2 - α )-3sin(π/2 + α)}

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已知tanα=2,求值 {4sin α( π- α)+3cos( π+α )}/ {4cos(3π/2 - α )-3sin(π/2 + α)}

已知tanα=2,求值 {4sin α( π- α)+3cos( π+α )}/ {4cos(3π/2 - α )-3sin(π/2 + α)}
已知tanα=2,求值 {4sin α( π- α)+3cos( π+α )}/ {4cos(3π/2 - α )-3sin(π/2 + α)}

已知tanα=2,求值 {4sin α( π- α)+3cos( π+α )}/ {4cos(3π/2 - α )-3sin(π/2 + α)}
{4sinα( π- α)+3cos( π+α )}/ {4cos(3π/2 - α )-3sin(π/2 + α)}
=(4sinα-3cosα)/(-4sinα-3cosα)
=-(4tanα-3)/(4tanα+3) (分子分母除以-cosα)
已知tanα=2
原式=-(4*2-3)/(4*2+3)
=-13/19