sin²2x-sin²4x=sin²3x-sin²5x1/2(1-cos4x)-1/2(1-cos8x)=1/2(1-cos6x)-1/2(1-cos10x)1-cos4x-1+cos8x=1-cos6x-1+cos10x(cos8x-cos4x)-(cos10x-cos6x)=0-2sin6xsin2x+2sin8xsin2x=02sin2x(sin8x-sin6x)=02sin2x*2sinxcos7x=0sin2x=0⇒2x=πn⇒x=πn/2sinx=0⇒x=πncos7x=0⇒7x=π/2+πn⇒x=π/14+πn/7Ответ x=πn/2 и x=π/14+πn/7