Sin^2x+4sinxcosx=5cos^2x

Question

Sin^2x+4sinxcosx=5cos^2x

Answer 1

Sin^2x+4sinxcosx=5cos^2x
tg^2x+4tgx=5
tg^2x+4tgx-5=0
tgx=1  tgx=-5
x=П/4+Пk
x=-arctg(5)+Пk