Question

Помогите решить уравнение по тригонометрии под а)

Answer 1

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Answer 2

3cos²x-2sin2x+sin²x=0
3cos²x-4sinxcosx+sin²x=0 /cos²x≠0
tg²x-4tgx+3=0
tgx=a
a²-4a+3=0
a1+a2=4 U a1*a2=3
a1=1⇒tgx=1⇒x=π/4+πn
a2=3⇒tgx=3⇒x=arctg3+πn