Question

Найдите Tg^2 а, если 4sin^2 a+9cos^2 a=6

Answer 1

 4sin^2 a+9cos^2 a= 6sin^2 a+6cos^2 a
4sin^2 a+9cos^2 a- 6sin^2 a-6cos^2 a=0
-2sin^2 a+3cos^2 a=0

-2sin^2 a/cos^2 a+3=0
-2tg^2a=-3
tg^a=-1,5