3sin2 x + 10sin x cos x + 3cos2 x = 0

Question

3sin2 x + 10sin x cos x + 3cos2 x = 0

Answer 1

3sin2 x + 10sin x cos x + 3cos2 x = 0

sin(2x)=x(-3sin(2)/5-3cos(2)/5)

3x sin(2)+5sin(2x)+3x cos(2)=0

5 sin(2x)+3x (sin(2)+cos(2))=0

x=-2,68301

x=-1,86266

x=0

x=1,86266

x=2,68301

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