Question

$\frac{4 \cos( \alpha ) - \sin( \alpha ) }{2 \sin( \alpha ) + \cos( \alpha ) }$
Если
$\cot( \alpha ) = 3$
​

Answer 1

$\frac{4Cos\alpha-Sin\alpha}{2Sin\alpha+Cos\alpha} =\frac{\frac{4Cos\alpha}{Sin\alpha}-\frac{Sin\alpha}{Sin\alpha}}{\frac{2Sin\alpha}{Sin\alpha}+\frac{Cos\alpha }{Sin\alpha}}=\frac{4Ctg\alpha-1}{2+Ctg\alpha}=\frac{4*3-1}{2+3}=\frac{11}{5}=2,2$