Question

при tga=2
3sina-2cosa/4sina+cosa
​

Answer 1

$tg(a) = 2$

$tg(a) = \frac{\sin(a)}{\cos(a)}$

$\frac{3\sin(a) - 2\cos(a)}{4\sin(a) + \cos(a)} = \frac{\frac{3\sin(a) - 2\cos(a)}{\cos(a)}}{\frac{4\sin(a) + \cos(a)}{\cos(a)}} =$

$= \frac{3\frac{\sin(a)}{\cos(a)} - 2}{4\frac{\sin(a)}{\cos(a)} + 1} =$

$= \frac{3tg(a) - 2}{4tg(a) + 1}  = \frac{3\cdot 2 - 2}{4\cdot 2 + 1} =$

$= \frac{4}{9}$