Question

- cos 3a/cos a+sin 3a/sin a=2

Answer 1

$-frac{cos3 alpha }{cos alpha }+frac{sin3 alpha }{sin alpha }=frac{sin3 alpha cos alpha -cos3 alpha sin alpha }{sin alpha cos alpha }=frac{sin(3 alpha - alpha )}{frac{1}{2}sin2 alpha }=frac{2sin2 alpha }{sin2 alpha }=2$

Answer 2

спасибо вам огромное

Answer 3

1+сos 2a+2sin"a=2