sin2x+cos2x=0=> sin2x=-cos2x|* \frac{1}{cos2x} =>tg2x=-1=>2x=- \pi /4+n \pi => x=- \pi /8 + n\pi/2" alt="3sin2x+3cos2x=0 => sin2x+cos2x=0=> sin2x=-cos2x|* \frac{1}{cos2x} =>tg2x=-1=>2x=- \pi /4+n \pi => x=- \pi /8 + n\pi/2" align="absmiddle" class="latex-formula">