Question

tg2a+tga=???????????????????

Answer 1

$a); ; tg2a+tga=frac{2tga}{1-tg^2a}+tga=frac{2tga+tga-tg^3a}{1-tg^2a}=frac{3tga-tg^3a}{1-tg^2a}=frac{tga(3-tg^2a)}{1-tg^2a}$

$b); ; tg2a+tga=frac{sin(2a+a)}{cos2acdot cosa}=frac{sin3a}{cos2acdot cosa}$